Arctic Sea Ice : Forum

Cryosphere => Permafrost => Topic started by: Tom_Mazanec on August 22, 2020, 03:20:18 PM

Title: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Tom_Mazanec on August 22, 2020, 03:20:18 PM
Here is the new thread, Oren.
Title: Re: 2020-2021 winter snow northern hemisphere
Post by: Ktb on August 25, 2020, 06:29:50 AM
Can naming conventions stay the same year to year. Please. It makes things so much easier.

Northern Hemisphere Winter 2019-2020 Snowcover / Misc Obs

to

Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on August 25, 2020, 07:10:41 AM
Fixed.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Tom_Mazanec on August 25, 2020, 12:23:26 PM
Yeah, I did this from my iPhone. Thanks for renaming.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: be cause on August 25, 2020, 12:48:08 PM
snow is accumulating on the ice ?
 https://modeles.meteociel.fr/modeles/gfs/run/gfsnh-16-6.png?6  .. b.c.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: be cause on August 25, 2020, 12:52:04 PM
so they don't get lost again .. from tealight ..

Some time ago I posted regional snow extents, but the topic is kind of lost in the depth of the forum. After some minor improvements and adding two new regions in Asia I created a seperate webpage for the data. It makes it easier to analyse than several different forum posts.

On the snow-cover webpage, featuring snow maps I added the long term NOAA data since 1967. The low 200km resolution looks terrible compared to the new 24km, but the longer timespan is better to judge changes over time.

https://cryospherecomputing.tk/Snow-Cover
https://cryospherecomputing.tk/snow-regional
Report to moderator    Logged
https://cryospherecomputing.tk/
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Niall Dollard on August 26, 2020, 12:27:31 AM
Lots of bright new snow has fallen over Axel Heiberg and the Ringnes Islands in the CAA.

Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on August 27, 2020, 09:04:43 PM
Yikes. I anticipate a record or near-record September advance in North America.

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020082712/ecmwf_T850_namer_11.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: igs on August 27, 2020, 10:48:50 PM
Yikes. I anticipate a record or near-record September advance in North America.

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020082712/ecmwf_T850_namer_11.png)

I hold against it and if it's only for the sake of you saing "I expect" in relation to the fact that this forecasts like more or less most of your snow forecasts, just to make points that never are going realize, are and have been 10 days out over many years.

Using forecasts 10 days out is a nice tool to hype anything that never happens, exactly like i can tell that those forecasts almost never become true.

<Removed judgemental part. Clarified snow not general forecasts. O>
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on August 27, 2020, 11:49:28 PM
I thought of bbr when I found a new paper - Severe Cold Winter in North America Linked to Bering Sea Ice Loss

I posted it here...
https://forum.arctic-sea-ice.net/index.php/topic,596.msg283603.html#msg283603
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on August 28, 2020, 12:26:25 AM
Yikes. I anticipate a record or near-record September advance in North America.

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020082712/ecmwf_T850_namer_11.png)

I hold against it and if it's only for the sake of you saing "I expect" in relation to the fact that this forecasts like more or less most of your forecasts, just to make points that never are going realize, are and have been 10 days out over many years.

Using forecasts 10 days out is a nice tool to hype anything that never happens, exactly like i can tell that those forecasts almost never become true.
My posts in the melt thread this season have been spot on. Your personal attack comes with no analysis and is not positive to generating analytical discourse.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on August 28, 2020, 03:17:44 AM
It's true that 10-day forecasts are not worth much, and that bbr has posted his share of them in the past. It's also true that their use has gone down sharply this year after re-registration. Igs and all, please avoid attacking users for past behavior, and for well-known behavior as well.
bbr - if you want to continue posting 10-day forecasts in the snow thread, that is less of an issue compared to the melt season thread where it's a big no no. However, I would strongly recommend following up 10 days later and reporting whether said expectations were fulfilled or not. This will greatly increase the value of such postings. In addition, maybe we will discover that for continental snow the 10-day is more reliable than for Arctic ocean weather.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on August 30, 2020, 12:46:40 AM
Yikes

The d8 forecast is pretty similar to what i posted before, but the d10 output....

(https://www.tropicaltidbits.com/analysis/models/gem/2020082912/gem_z500aNorm_nhem_41.png)

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020082912/ecmwf_z500aNorm_nhem_11.png)

It looks like snows should really begin in force imminently across the highest Rockies, the Mackenzie Range, Alaska, and much of the Canadian tundra.

The GFS offers a somewhat diff look (and is probably the most incorrect of them all) but is still frigid.

(https://www.tropicaltidbits.com/analysis/models/gfs/2020082918/gfs_z500aNorm_nhem_40.png)

I am beginning to become very concerned about potential agricultural impacts. The CMC is IMO the best for North America this time of year, EURO also good. But CMC is good at ice and snow dynamics, esp advance (IMO) which is why it is ideal for September / October / November (altho globally it may still underperform, it is designed for Canada, so.....)

(https://www.tropicaltidbits.com/analysis/models/gem/2020082912/gem_T2m_us_41.png)

Note the attached EURO snowfall from weather.us is through D10 and not just D10!
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 01, 2020, 09:00:38 PM
Yikes. I anticipate a record or near-record September advance in North America.

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020082712/ecmwf_T850_namer_11.png)
The 120hr forecast is remarkably consistent to the D10 forecast! And today's 12z EURO shows more potent Greenland airmasses mixing into the Arctic waiting to descend into North America as well, with more energy from recurving typhoons pumping a PIG ridge into Bering / Chukchi...

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020090112/ecmwf_T850_namer_6.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 01, 2020, 09:05:24 PM
PS,

Day 8, the 12z EURO has a major snowstorm in the lower Rockies, with snows into Denver and accumulations all the way into the TX panhandle. That would be fairly unprecedented for September 8th, I believe, Denver's earliest on record is actually about 4" on 9/3/1961, but its #2 was on 9/8/1962 and that was under an inch.

https://weather.us/model-charts/euro/colorado/acc-precipitation-snow-total/20200911-1200z.html
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 02, 2020, 08:38:06 PM
Major blizzard now D5-6 in Rockies, amounts much higher, and over the more "normal" center of cold anomalies as of late (Montana and vicinity).

https://weather.us/model-charts/euro/2020090212/usa-west/acc-precipitation-snow-total/20200909-0000z.html
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 02, 2020, 08:56:25 PM
So, it is worth noting --

The EURO has done WELL with cold forecasting in North America so far this week or two. The D10 forecast posted previously is going to come pretty close to verifying (not perfect, but the overall look was very accurate).

The EURO is now hinting at another vortex of Greenland air rotating into the Arctic and down into North America by day 10 or so. At D9 you can see it here still over Beaufort.
 
(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020090212/ecmwf_T850_namer_10.png)

You can also see the atmospheric trace of event #1 still extant in the Rockies. It is more obvious when looking at 2M temps, but the snow is so deep from the first blizzard that a good portion would PROBABLY survive til the next wave arrives (around the 13th or so?). This would accrete to what has already fallen in many areas, further dropping the snow line in the Rockies, and establishing a firm foothold for winter 2020-21 to take root on the North American continent.

Finally, this early and anomalous mid-latitude albedo event is likely going to evacuate an enormous amount of heat from the Pacific and Gulf of Mexico poleward in varying directions (IMO) and these evacuations will worsen as the anomaly grows in area and extent. Prepare for heat blasts into the Arctic from all directions, aided significantly by this potentially widespread appearance of snowfall around 40-45N in North America (which, interestingly, is proximate to my post in the ice age thread re: the Rockies matching the Himalayan anomaly.... but that is another subject).
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 03, 2020, 01:47:40 PM
The 00z EURO was worse than the 12z, IMO. The Rockies blizzard in the D5 period is now forecast to produce 4"+ in Denver and 2"+ in Albuquerque. At 00z yday, amounts were substantial over highest Rockies, at 12z yday, amounts increased and spread to MT / WY, at 00z today, amounts increased further but switched from MT + WY + CO to CO + WY + NM (primarily).

New Mexico is..... SOUTH. I think such a September event would be unprecedented (or almost unprecedented, certainly with currently +oceanic heat content) for the Lower High Rockies.

https://weather.us/model-charts/euro/usa-west/acc-precipitation-snow-total/20200913-0000z.html
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 03, 2020, 06:45:29 PM
Yikes for agriculture....
(https://www.tropicaltidbits.com/analysis/models/gem/2020090312/gem_T2m_us_29.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 04, 2020, 06:15:47 PM
Now creeping into the Plains. I am very worried about this September.


(https://www.tropicaltidbits.com/analysis/models/gfs/2020090412/gfs_asnow_us_26.png)

The 00z EURO might have been even worse.

https://weather.us/model-charts/euro/usa-west/acc-precipitation-snow-total/20200914-0000z.html
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 04, 2020, 08:55:39 PM
Long range modeling is looking.... COLD

The Bering Sea connection has to be a major factor here but I guess this year maybe Laptev, ESS are aiding (???)

(https://www.tropicaltidbits.com/analysis/models/gem/2020090412/gem_z500aNorm_nhem_41.png)

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020090412/ecmwf_z500aNorm_nhem_10.png)

All the polar air keeps draining into North America, but by the end of the period it is also happening again over Kamchatka and NE Siberia. Meanwhile, it looks like the advected heat from the Rockies blizzard (now D4) arrives on the ATL front by day 8-10 on the 12z CMC, and accompanies a GAAC that is almost 1050MB (!!!). The extreme WARMTH dominates the entirety of the CAB by D10 and for mid-September, that would be very impressive, though it is Day 10 and the CMC.

I do think with the Rockies event now drawing near, we can consider such a scenario more LIKELY than it would be if depicted otherwise.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 04, 2020, 09:01:37 PM
The next major Rockies snow event arrives D10 on the North Slope of the Yukon / NWT. Wow. I think this will also end up more impressive than modeled and could also possibly arrive sooner. This would probably be a Rockies storm by D12ish.

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020090412/ecmwf_T850_namer_11.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 06, 2020, 06:24:28 PM
As depicted, I would now call the upcoming event "unprecedented" in its scope, depth, and duration for areas impacted given the time of year. We are now seeing snows forecast to spread well into the High Plains, all the way to the middle of Nebraska and Kansas...

(https://www.tropicaltidbits.com/analysis/models/namconus/2020090612/namconus_asnow_us_29.png)

(https://www.tropicaltidbits.com/analysis/models/gfs/2020090612/gfs_asnow_us_20.png)

(https://www.tropicaltidbits.com/analysis/models/gfsp/2020090600/gfsp_asnow_us_25.png)

Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 06, 2020, 10:31:30 PM
The CMC shows major areas of >32F daytime temps developing by D10 across AK, the NW Territories, Yukon, and Quebec. As well as parts of the Shield and the elevated Rockies. Snowfalls by D10 are overspreading increasingly broad areas of North America though their duration remains tenuous outside of areas of greatest depth and elevation (for now).

(https://www.tropicaltidbits.com/analysis/models/gem/2020090612/gem_asnow_namer_40.png)

I think the EURO is shunting too much cold towards Siberia in the extended and it is probably going to fall into the Rockies. We will see if it adjusts but it is also cold along North Facing-slopes of the NW continental areas, as well as Quebec and the Shield.

With the impending airmass around 9/15 looking to be substantially below 32F even during daytime, if it arrives overtop the Rockies a few days thereafter, the snows could be even larger than round 1, and much more geographically uniform (i.e. across the entire High Plains and maybe the Upper Midwest). We will see what happens but I think there is a good chance North America sees one of its snowiest Septembers ever.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on September 09, 2020, 12:09:23 PM
GFS says its damn cold in that patch of the USA this morning, but by Saturday.....

Meanwhile still plenty of warmth over most of North America.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 12, 2020, 09:19:30 PM
While some snows will fall over Canada through D10, melting in some spots and starting to stick in favored elevations, the big story today is an event shown on the 12z EURO around D8-10. Snows begin in Maine and New England by D10 on the NW side of the phasing hurricane / polar vortex and it is backing into the coast at that hour.

The solution will probably disappear, but the EURO has a knack for major cyclonic events in this season (it was the first to show Sandy) so it will be interesting to watch its evolution over the next few days and this may bear watching.

(https://www.tropicaltidbits.com/analysis/models/ecmwf/2020091212/ecmwf_T850_us_11.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on September 13, 2020, 01:41:47 AM
72F in Denver as I type so that snow melted rather quickly. There was one disaster as a result of the freeze and snow. Millions of dollars of marijuana crops were destroyed.

https://mjbizdaily.com/early-freeze-in-colorado-could-cost-marijuana-hemp-growers-millions-in-losses/
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: be cause on September 13, 2020, 11:29:36 AM
.. while those in Mendocino , California go up in smoke ...
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on September 24, 2020, 05:22:58 PM
https://ccin.ca/ccw/snow/current

North America - the snow came, it melted. It does that in September.

Eurasia - almost zero new snow.

Early days - climate scientists suggest a long-term trend of later snow and more of it.
And a winter Al Nina is supposed to mean a cold North America - at least above 40? 45? 50? North.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on September 26, 2020, 12:47:07 AM
Through D10 modeling is now showing major SWE accreting in elevated areas of Quebec as well as the Rockies and Alaska. By D10, many models are now showing extreme 500MB blocking developing across much of the Arctic, centered atop the greatest oceanic heat anomalies derivative of the melt season. This is extremely concerning, IMO, and while extended guidance from the GFS posted below *should not be taken at face value* I think that combined with the looks being printed by ECMWF / CMC, alarm bells are ringing for possible anomalous snowfalls and severe October cold spells in the mid-latitudes.

(https://www.tropicaltidbits.com/analysis/models/gfs/2020092518/gfs_z500aNorm_nhem_46.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on October 02, 2020, 06:47:36 PM
So far this year's snowfall is more in Eurasia than North America, where snowfall is very much at average.

But it is very early days as yet.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Niall Dollard on October 04, 2020, 02:05:31 PM
Day 277 compared with last year. (needs a click)

Very little yet in eastern Siberia.

Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on October 13, 2020, 01:37:17 AM
The snowfall response this year, surprisingly and contrary to my thoughts, has so far been anemic -- or it had been before about yesterday. Looks like accretion and spread of the snowpack begins substantially over the next week over both Eurasia and North America.

I guess the record warm Laptev et al have overwhelmed the Eurasian snowfall response until this point (?) due to high latitude blocking? But perhaps as the snowfalls actually begin the depths will accrete more than normal and do so quite rapidly, who knows!
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on October 16, 2020, 03:56:13 PM
How average can you get? https://cryospherecomputing.tk/ from Nico Sun
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on October 21, 2020, 03:11:32 AM
Welp, here we are, the cascade is happening in force again it seems.

(https://drive.google.com/uc?id=1WmpWVrVyk3oYqAezG3c16lPq-jyJpvSx&export=download)

North America is up to +2SD suddenly and looks like it should end the month at a record high (IMO).
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on October 27, 2020, 03:17:36 PM
How average can you get? https://cryospherecomputing.tk/ from Nico Sun

Until it's not average any more - at least in North America.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on October 27, 2020, 03:39:25 PM
October might end at a massive all-time record for North America. The animated Canuck maps are a day ahead of the graphs. The uptick today was again.... absolutely insane, and occurring across MANY of the elevated areas of the continent.

https://weather.gc.ca/saisons/animation_e.html?id=month&bc=sea

Winter is most definitely here.

(https://hprcc.unl.edu/products/maps/acis/7dTMAXDeptUS.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on October 27, 2020, 10:29:24 PM
Very much not average. Record breaking cold across the center of the U.S. with a lot of snow and ice storms as far south as Oklahoma. Miserable weather in Chicago with lows around 0C.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on October 28, 2020, 02:18:09 PM
Very much not average. Record breaking cold across the center of the U.S. with a lot of snow and ice storms as far south as Oklahoma. Miserable weather in Chicago with lows around 0C.
This is insane.

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_sce.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Tor Bejnar on October 28, 2020, 02:20:39 PM
If the winter weather continues for another week, it will suppress the vote a little.  On one hand, 'they are used to it'; on the other, 'it's early.'  Several of the most affected states have competitive federal office races.  There will also be competitive state and local offices, and some 'interesting' ballot initiatives (https://ballotpedia.org/2020_ballot_measures).
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: be cause on October 28, 2020, 03:33:50 PM
winter will have forgotten it's visit to the states by election day ...
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Tealight on October 28, 2020, 03:34:46 PM
The positive snow anomaly in North America of 4.430 million km2 is very close to the record anomaly. On 11th and 12th October 2009 had an anomaly of +4.533 million and +4.715 million respectively. The only other close year was 2014 with +3.956 million on November 15th.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on October 28, 2020, 04:19:20 PM
winter will have forgotten it's visit to the states by election day ...

In the lower 48 snow starts to melt tomorrow and Nov 3rd looks like a really pleasant day
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on October 29, 2020, 04:26:58 AM
Please don't go OT re elections.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on October 29, 2020, 02:54:23 PM
The positive snow anomaly in North America of 4.430 million km2 is very close to the record anomaly. On 11th and 12th October 2009 had an anomaly of +4.533 million and +4.715 million respectively. The only other close year was 2014 with +3.956 million on November 15th.
Did we pass 2009's anomaly today? The numbers are up again... we may have a new record here!

It should be noted 09-10 and 14-15 were both El Nino winters (moderate, and weak). We are in Nina-ish conditions now.

It should also be noted that the NHEM snow anomaly (+3.781M KM^2) is now larger than the sea ice deficit (-2.1M KM^2). By a decent margin, to boot. Who says the Earth-climate-system doesn't have built in resiliency measures....? It just so happens that the resiliency of the planet comes at the cost of most of our civilization. Oh well!
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on October 31, 2020, 03:19:02 PM
The freshwater flux is now well underway in North America and I would say the melting of this extremely anomalous event is giving us our first meltwater pulse of the season. Though it is not substantial compared to the spring melt it is still an important process in lowering ambient temperatures of rivers, lakes, and adjacent saltwater bodies when runoff does arrive. SSTs are now cooling rapidly in the Gulf of St. Lawrence and parts of Hudson Bay, with shore ice also forming along much of Hudson Bay.

Given the extended forecast I anticipate a relatively early Hudson refreeze this year with most of the Bay frozen by 11/20 - 12/1. I wonder how this will act in concordance with the latest-ever-open areas of the Siberian-adjacent seas re: atmospheric impacts come December and onwards (and also in sync with what will probably be +SWE and +SCE anomalies).
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on October 31, 2020, 05:11:26 PM
Central Park and the rest of the reporting stations in NYC recorded a trace of snow yesterday, setting the record for the shortest length of time between measurable snowfalls, coming on the heels of our last T on May 9th. Five months, and three weeks. !
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on October 31, 2020, 06:32:38 PM
What goes very impressively up may go as equally impressively down.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on November 03, 2020, 02:17:24 AM
While SCE is only now stabilizing, SWE rebound is already well underway and it dipped much less (relatively). This shows how potent albedo can be as an insolation modifier early / late in the winter season -- it takes barely any relative precipitation to cover a HUGE continental area to massive deflection of proportional insolation. Even if these incursions of snowfall are short-lived for the time being, their scale makes them quite effective at dissipating sunlight (and heat).

Simultaneously, their OCCURRENCE is a dissipation of heat (from the Arctic Ocean) so they are doubly advantageous. Or perhaps even more efficacious than Arctic Sea Ice at resolving +OHC when the sea ice peels back even further. Oh dear. Let's hope not.

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_swe.png)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on November 03, 2020, 02:31:19 AM
Also, if the EURO is correct it looks like Foxe Basin will be totally iced over by D10 and much of Hudson will be following suit at a rapid pace. There is a chance most of Hudson Bay will ice by 11/15-20, which would be very early. 11/25 is more reasonable which is still 1980s ish.

This would probably anchor a -500MB area in North America accompanied by associated negative temp anomalies, I think this would also advect a major amount of heat into both PAC and ATL fronts but esp the ATL fronts as Baffin is also icing over very quickly while Laptev, Kara, and Barentz are not. They will probably bear the brunt of poleward heat transport derivative of the continental and sea ice anomalies impending in aforementioned regions (IMO) as these anomalies are upwind of an Atlantic Ocean that has a LOT of heat to send poleward.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on November 03, 2020, 07:38:15 PM
What goes very impressively up may go as equally impressively down.
So far not quite so impressively down...
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on November 04, 2020, 02:45:48 AM
Also, if the EURO is correct it looks like Foxe Basin will be totally iced over by D10 and much of Hudson will be following suit at a rapid pace. There is a chance most of Hudson Bay will ice by 11/15-20, which would be very early. 11/25 is more reasonable which is still 1980s ish.

If anything, Hudson ice is actually late this year, so I'll take the opposite side of the bet. UH AMSR2 shows virtually zero ice area where in quite a few previous years it reached 50k-100k km2.
I assume you plan to revisit this forecast when it comes due?
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on November 04, 2020, 03:15:36 AM
Also, if the EURO is correct it looks like Foxe Basin will be totally iced over by D10 and much of Hudson will be following suit at a rapid pace. There is a chance most of Hudson Bay will ice by 11/15-20, which would be very early. 11/25 is more reasonable which is still 1980s ish.

If anything, Hudson ice is actually late this year, so I'll take the opposite side of the bet. UH AMSR2 shows virtually zero ice area where in quite a few previous years it reached 50k-100k km2.
I assume you plan to revisit this forecast when it comes due?
The Canucks are more accurate there has been lots of cloud interference /

(https://ice-glaces.ec.gc.ca/prods/WIS54CT/20201102180000_WIS54CT_0011304996.gif)

It is going to be advancing rapidly next few days it is not obvious yet but wait til end of month and compare, maybe I'm wrong, we shall see.

(https://ice-glaces.ec.gc.ca/prods/WIS54DPTCT/20201102180000_WIS54DPTCT_0011305087.gif)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on November 04, 2020, 03:23:48 PM
The meteo people tell us that Al Nina years are associated with a cold Canada.
A recent science paper claims an association between low Bering Sea winter ice and a cold Canada.
Environment Canada has a forecast of a pretty cold November for much of Canada

An early freeze of Hudson Bay by a few days  is very possible, but so what? Hudson Bay has pretty much ignored AGW so far.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 04, 2020, 06:02:52 PM
Snow extent is crashing, and a continued warm week ahead is forecasted for North America and Eastern Europe/Western Siberia.  NH Snow extent anomaly is already -1.8 million km^2 according to Cryosphere Computing, and bound to crash further.  That's some additional albedo feedback right there that should postpone the onset of deep winter cold for much of the arctic. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 06, 2020, 04:37:05 PM
NH Snow extent anomaly now (11/5/2020) -2.392 million km^2 according to Cryosphere Computing.  It's a bit surprising considering all the open water in the Arctic seas, but it's just too warm in North America and Eastern Europe / Western Siberia for precipitation to fall as snow quite yet. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 07, 2020, 04:50:45 PM
A little bit of a dip today back to "only" a -2.1 million km^2 anomaly for NH snow cover extent.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 08, 2020, 05:33:38 PM
NH Snow extent anomaly now (11/7/2020) -2.987 million km^2 according to Cryosphere Computing. 

Weather is not the same as climate, but if re-glaciation in the northern hemisphere is indeed going to happen as per bbr's predictions (doubtful, in my opinion), it looks like it won't be a straight trend without notable reverses or exceptions...
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on November 08, 2020, 05:42:21 PM
Just to mention that the reglaciation issue is not to be mentioned or discussed, or goaded.  It is wrong and does not need discussion (except in one designated thread which did not find much interest).
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on November 09, 2020, 01:45:15 PM
The climate scientists tell us that global heating means that snowfall will be later starting up in lower latitudes but overall there is going to be more of it.

November 8th data & map supports that - especially Europe & Western Siberia.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 09, 2020, 10:42:32 PM
NH Snow extent anomaly now (11/8/2020) -3.184 million km^2 according to Cryosphere Computing.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 12, 2020, 07:15:43 PM
Some decent snowfalls in the upper Midwestern U.S. and around the Ural region of Russia, but NH snow extent anomaly still (11/11/2020) -1.842 million km^2 according to Cryosphere Computing.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 13, 2020, 04:24:09 PM
11/12/2020 NH snow extent anomaly according to Cryosphere Computing:  -2.191 million km^2. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: SimonF92 on November 13, 2020, 07:55:57 PM
Just to mention that the reglaciation issue is not to be mentioned or discussed, or goaded.  It is wrong and does not need discussion (except in one designated thread which did not find much interest).

Its dangerous to say that is it "wrong". In the 60s, if you mentioned "global warming" youd have been told you were wrong.

I understand its banned because it is pretty wild, but that doesnt mean its wrong.

Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: be cause on November 14, 2020, 11:18:40 AM
so bbr has had the canadian ice sheet growing for the last 6 years .. just go back to 2016 freezing season or the like and read ad nauseum .. we need little refreshment annually .
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on November 14, 2020, 03:12:41 PM
so bbr has had the canadian ice sheet growing for the last 6 years .. just go back to 2016 freezing season or the like and read ad nauseum .. we need little refreshment annually .
Record North American extent and volume are dismissed because posters here don't know the difference between hemispheres and continents.

My reply is moderated and in red.

So why should I keep participating here.

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_sce.png)

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_swe.png)

And you just attacked me as well. I bothered logging back in to say this but maybe next time I won't, I am pretty over this.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on November 14, 2020, 03:26:08 PM
Just to mention that the reglaciation issue is not to be mentioned or discussed, or goaded.  It is wrong and does not need discussion (except in one designated thread which did not find much interest).

Its dangerous to say that is it "wrong". In the 60s, if you mentioned "global warming" youd have been told you were wrong.

I understand its banned because it is pretty wild, but that doesnt mean its wrong.

OK. It's just unsupported completely by any relevant science.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: kassy on November 14, 2020, 05:11:18 PM
His theory and the actual science it is derived from are two different things. Discussing the actual science is ok.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on November 14, 2020, 08:50:58 PM
Folks, reglaciation is to be discussed only in the designated thread. If anyone has trouble finding it I can post a link later. If anyone wants to explore the science or lack thereof, feel free to do so over there.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on November 14, 2020, 08:52:11 PM
Record NA snowfall is certainly welcome to be discussed here.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 16, 2020, 04:58:16 PM
11/15/2020 NH snow extent anomaly according to Cryosphere Computing:  -1.592 million km^2.

European Russia FINALLY getting some snow, but some retreat in east Asia and North America. 

Kids decades from now (or even right now) are going to read about the Kronstadt rebellion during the Russian Civil War, and scratch their heads over how the Red Army was able to send cavalry over the frozen ice in March from Petrograd to the Kronstadt naval base, unless it is explicitly explained to them that the climate used to be different.  Or likewise, they are going to be scratching their heads over why Operation Typhoon in November of 1941 was so difficult meteorologically for the German Wehrmacht. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: El Cid on November 16, 2020, 06:04:51 PM
  Or likewise, they are going to be scratching their heads over why Operation Typhoon in November of 1941 was so difficult meteorologically for the German Wehrmacht.

...and they will be told that it was unseasonally, unexpectedly  unbelievably cold during 1941 Nov and Dec in Eastern Europe and Russia as shown in the attachement. It was one of the coldest winters of the century.  It was 4-5 C colder in November and December than the average of that era! Even October was 2-3 C colder. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on November 19, 2020, 06:39:03 PM
North America snow @ 18 Nov from https://ccin.ca/ccw/snow/current

SCE about 1 SD above average,
SWE very much above average.

which seems to be the patttern for early winter in recent years.

Mind you, if the centre and north of North America gets really cold (due to Al Nina and low winter sea ice in the Bering) perhaps it could get too cold for snow.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 19, 2020, 09:28:45 PM
For the record, total Northern Hemisphere snow extent is still below average.  According to Cryosphere Computing, for 11/18/20 it is -0.582 million km^2. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 21, 2020, 11:49:31 PM
For the first time in a while this year, total Northern Hemisphere snow extent is going significantly above average.  According to Cryosphere Computing, for 11/20/20 it is +0.510 million km^2.

Total combined northern hemisphere snow + ice extent is still barely below average, but most of that below-average ice extent is in the Kara Sea where the sun isn't shining anyways, so now finally the winter snow is getting some positive albedo feedback to deepen cold temperatures and snow extent further.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on November 23, 2020, 06:48:47 PM
11/22/2020 NH snow extent anomaly according to Cryosphere Computing:  +1.236 million km^2. 

Quite a burst of snowfall in Eurasia!
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: The Walrus on November 26, 2020, 04:27:11 PM
A major snowstorm is developing in the U.S.  Expect big changes next week.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on December 08, 2020, 07:28:33 PM
https://ccin.ca/ccw/snow/current

Snow as at 7 Dec

Eurasia SCE pretty much average, SWE pretty much usual 1SD and more abovwe average.

North America a surprise?
SCE more or less stalled in the lat 3 weeks while SWE stays well above +1S above average.
My speculations are
- a mostly warm USA means not so much snow cover,
- but in the North of Canada that relative warmth means more moisture but falling as snow - hence above average SWE.

My speculation for the rest of winter is for NA is December stays warmish but Jan to March will be bloody cold, so cold in Canada that there won't be a lot of snow there but maybe loads in the lower 48..
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on December 08, 2020, 09:43:35 PM
Any word on what happened with the Cryosphere Computing website?  It is still down for me.  It's my go-to resource for charting the snow extent anomaly.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: SimonF92 on December 08, 2020, 11:17:52 PM
Any word on what happened with the Cryosphere Computing website?  It is still down for me.  It's my go-to resource for charting the snow extent anomaly.

Hes migrating the site i believe, Kassy linked the thread yesterday

https://forum.arctic-sea-ice.net/index.php/topic,3350.0.html
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on December 10, 2020, 03:52:09 PM
Good, now that Cryosphere Computing is back online, I can check the NH snow extent anomaly.  For 12/9/2020, it is -1.220 million km^2.  Above average snow extent in Asia, way below average snow extent in North America currently.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on December 23, 2020, 03:45:59 AM
On the solstice (12/21/20), NH snow extent anomaly was -2.107 million km^2. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on December 24, 2020, 07:33:21 PM
https://ccin.ca/ccw/snow/current as at 23rd December

Environment Canada graphs say for both North America and Eurasia, while Snow Cover Extent (SCE) is below Average, Snow Water Equivalent (SWE) i.e. mass, is well above average.

It is Europe and the Lower 48 especially that are short of snow.

But 3-4 months to go.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on December 30, 2020, 10:59:40 PM
On 12/29/20, NH snow extent anomaly was -1.438 million km^2.

NH snow extent has been consistently below average over the past week.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on January 05, 2021, 07:51:01 PM
On 1/04/21, NH snow extent anomaly was -2.028 million km^2 according to Cryosphere Computing.

NH snow extent has been consistently below average over the past week.  15 days past the winter solstice, days are now getting meaningfully longer each day in the northern hemisphere, and lack of snow extent starts to matter more and more as an albedo jumpstart for the spring thaw and melt ponding. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on January 06, 2021, 01:30:06 PM
https://ccin.ca/ccw/snow/current as at 5 jan 2021

Environment Canada graphs say for both North America and Eurasia, while Snow Cover Extent (SCE) is at or below Average, Snow Water Equivalent (SWE) i.e. mass, is well above average.

But still 3-4 months to go, and a developing SSW that could disrupt things a lot.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on January 06, 2021, 05:17:10 PM
Wouldn't a breakdown of the polar vortex tend to increase NH snow?
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on January 06, 2021, 06:17:25 PM
Wouldn't a breakdown of the polar vortex tend to increase NH snow?
At which point one asks - where is/are the climate scientist/s when you need one/them?

But a long article on Neven's blog from way back in 2013 can be found @ https://neven1.typepad.com/blog/2013/04/sudden-stratospheric-warmings-causes-effects.html
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: kassy on January 06, 2021, 08:40:54 PM
One of my old favorites. It all turns out be be really complicated.

Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on January 08, 2021, 12:09:18 AM
On 1/06/21, NH snow extent anomaly was -2.351 million km^2 according to Cryosphere Computing.

Northern hemisphere snow extent has been significantly below average for the past week.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on January 08, 2021, 10:04:09 AM
Thanks for these recurring updates, Comradez.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Sebastian Jones on January 10, 2021, 07:59:59 PM
A site I like to check regularly to watch snow cover is https://www.natice.noaa.gov/ims/
It appears to have gone off line.
Does anyone know of an alternative site?
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on January 10, 2021, 08:45:12 PM
A site I like to check regularly to watch snow cover is https://www.natice.noaa.gov/ims/
It appears to have gone off line.
Does anyone know of an alternative site?
This one?
https://www.ncdc.noaa.gov/snow-and-ice/extent/snow-cover/nhland/11

Lots of menu options
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: grixm on January 10, 2021, 10:21:05 PM
A site I like to check regularly to watch snow cover is https://www.natice.noaa.gov/ims/
It appears to have gone off line.
Does anyone know of an alternative site?

I like this one (scroll down a bit): https://cryospherecomputing.tk/
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on January 11, 2021, 07:47:45 PM
On 1/10/21, NH snow extent anomaly was -1.535 million km^2 according to Cryosphere Computing.

Northern hemisphere snow extent has been significantly below average for the past week.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on January 15, 2021, 07:28:43 PM
On 1/14/21, NH snow extent anomaly was -1.362 million km^2 according to Cryosphere Computing.

Northern hemisphere snow extent has been slightly below average for the past week. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on January 19, 2021, 01:00:34 PM
https://ccin.ca/ccw/snow/current

North America snowfall a really good exemplification of that AGW should reduce snow cover extent (SCE) at lower latitudes and and increase snow water equivalent, i.e. mass, (SWE) at higher latitudes (and elevation) until (as in the UK) it's just too warm for snow nearly all the time.

Similar but not as pronounced this year in Eurasia.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on January 19, 2021, 05:21:28 PM
On 1/18/21, NH snow extent anomaly was -1.096 million km^2 according to Cryosphere Computing.

Northern hemisphere snow extent has been slightly below average for the past week.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on January 26, 2021, 03:52:29 PM
On 1/25/21, NH snow extent anomaly was -2.018 million km^2 according to Cryosphere Computing.

Northern hemisphere snow extent has been significantly below average for the past week.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on January 31, 2021, 05:04:18 PM
On 1/30/21, NH snow extent anomaly was -1.374 million km^2 according to Cryosphere Computing.

Northern hemisphere snow extent has been slightly below average for the past week, hovering around the -1 million km^2 mark.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 03, 2021, 02:08:16 PM
https://ccin.ca/ccw/snow/current

Eurasia snow getting interesting. SWE (snow water equivalent = mass) still increasing at more than 1SD above average, while SCE (snow cover extent) continuing to decline to much more than 1 SD below average.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 04, 2021, 05:36:58 PM
On 02/03/21, NH snow extent anomaly was -1.703 million km^2 according to Cryosphere Computing.

At what point in February or March does a snow extent anomaly start to have a meaningful impact in terms of jumpstarting or delaying the spring melt via albedo feedback?  The North American Great Plains, Southern Russia, and the Balkans are starting to have significant and durable negative anomalies. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 05, 2021, 07:16:24 PM
On 02/04/21, NH snow extent anomaly was -2.101 million km^2 according to Cryosphere Computing.

In the Balkans and Southern Russia where the anomaly is the biggest (Roughly 45N), average daily temperatures have been hovering around 5C, and there are now more than 10 daylight hours each day, with the length of daylight increasing by more than 2 minutes each day. 

Bitter cold is coming to the Great Plains in North America this upcoming week, but it remains to be seen if there will be much precipitation associated with this cold wave in the Great Plains. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 06, 2021, 04:51:22 PM
On 02/05/21, NH snow extent anomaly was -2.443 million km^2 according to Cryosphere Computing.

If you compare snow coverage to last year on this date, there is surprisingly a very similar deficit in Eastern Europe/Southern Russia/Central Asia, although last year had positive snow extent anomalies in China and in North America that we do not see currently this year. 

Last year the snow extent deficit in Eastern Europe/Southern Russia/Central Asia remained remarkably consistent up through March.  Will we see something similar this year?
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 06, 2021, 05:11:13 PM
https://ccin.ca/ccw/snow/current

Nortern Hemisphere snow getting even more interesting. SWE (snow water equivalent = mass) still increasing at more than 1SD above average, while SCE (snow cover extent) continuing to decline to much more than 1 SD below average.

Will that extra snow mass in high latitudes delay the melt?

We have reached the point where at least in the lower latitudes new snow is likely to melt soon after. There is warmth now in that sun at least to the mid-50's latitude.

Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on February 06, 2021, 10:37:31 PM
https://ccin.ca/ccw/snow/current

We have reached the point where at least in the lower latitudes new snow is likely to melt soon after. There is warmth now in that sun at least to the mid-50's latitude.

Generally yes but the 10 inches of snow in Chicago area isn't going anywhere over the next 2 weeks as temperatures stay very cold.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 06, 2021, 11:15:51 PM
https://ccin.ca/ccw/snow/current

We have reached the point where at least in the lower latitudes new snow is likely to melt soon after. There is warmth now in that sun at least to the mid-50's latitude.

Generally yes but the 10 inches of snow in Chicago area isn't going anywhere over the next 2 weeks as temperatures stay very cold.
la Nina plus 3(?) SSWs is going to cause some oddities. And N America snowfall  is small beer compared with Asia
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: be cause on February 07, 2021, 01:56:40 AM
GFS's forecast suggests snow a plenty coming to N. America and Europe over the next 7-10 days . Snow to the Gulf coast and covering most of Italy and Greece as well as the British isles .. almost an ' event '.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 07, 2021, 05:25:53 PM
On 02/06/21, NH snow extent anomaly was -2.568 million km^2 according to Cryosphere Computing.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 09, 2021, 03:19:43 PM
On 02/08/21, NH snow extent anomaly was -1.209 million km^2 according to Cryosphere Computing.

Asia still very low, but Europe and N. America rebounding in snow extent with some mega cold snaps incoming for both. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: SimonF92 on February 09, 2021, 05:00:04 PM
Cant remember ever seeing the SWE below +1SD in winter, same thing this year. One year there was so much snow they had to adjust the y-axis scale
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 09, 2021, 07:19:59 PM
Cant remember ever seeing the SWE below +1SD in winter, same thing this year. One year there was so much snow they had to adjust the y-axis scale
Perhaps 2017-18? Not very good image attached.

Note that it did not delay the melt by very much.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: SimonF92 on February 09, 2021, 09:07:44 PM
Cant remember ever seeing the SWE below +1SD in winter, same thing this year. One year there was so much snow they had to adjust the y-axis scale
Perhaps 2017-18? Not very good image attached.

Note that it did not delay the melt by very much.

Ah yes, a little brush there. Look at that crazy fast melt in spring- must have been torched
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 13, 2021, 03:02:18 PM
On 02/12/21, NH snow extent anomaly was -0.754 million km^2 according to Cryosphere Computing.  Slightly below average. 

Snow extent has been accumulating in North America, but falling in Asia.  Still more snow to come in North America (what looks to be an historic snowfall with snow and freezing temps all the way down to Houston and Corpus Christi near the Gulf coast). 

Aaaaaand in other news, our heater just went out, while temperatures here in Missouri hover in the teens today and are set to plunge below zero Sunday and Monday.  We have a technician scheduled to come in a couple of hours.  House temp is 52 F and falling.  We have the electric stovetops on....
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 13, 2021, 06:15:04 PM
Yay!  Furnace fixed!  The drain that drains the inducer motor of moisture was frozen/clogged underneath the house, so water was backing up into the inducer turbine, which wasn't allowing the turbine to produce enough exhaust airflow, which wasn't allowing the ignition sensor to see that it was safe for the ignition and gas to turn on.  At first the technician thought that the entire inducer motor might have worn its bearings out (after 1 and a half years from when I bought it new?!) but nope, it was the moisture drain to it that was frozen shut underneath the house. 

Now we are ready for the -10 F low that we are forecast to have Tuesday morning...
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on February 13, 2021, 09:45:31 PM
Glad it's fixed.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on February 14, 2021, 08:29:43 PM
It took a while this year but... here we are.... it looks like we are about a week from breaking the scale.

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_swe.png)

Extent in North America is also now quite impressive, and we have... epic.... cold in the southern tier of the country. Unprecedented cold and snow in the Southern Plains, in fact.

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_sce.png)

Hemispherically, we have another month or more of accretion to go (probably), and we are already around +1SD vs. normal seasonal maximum. We will break this scale a bit later than North America's, but it looks like this one should fall as well.

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/nh_swe.png)

Spatially, the strong negative anomalies across Quebec that developed in the late autumn have now been completely resolved, now relegated to Newfoundland.

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/plot_anom_sdep.png)

Deficits appear concentrated in Southern Europe and the region of Eurasia below the Urals. In sync with the lack of ice along the CAB front / Barentz, I think this may portend an EARLY arrival of springtime and summer across much of Europe and western Eurasia, and a vigorous start to the melt season along the CAB's Atlantic boundary. However, the plentiful SWE elsewhere may combine with these anomalies in the High Arctic to PROLONG winter, perhaps severely so, across North America in particular -- and maybe the Himalayas and parts of Siberia again, especially adjacent to the very strong extent numbers in Okhotsk? We shall see.

I do think the very high +SWE is an indicator that this springtime may follow the trajectory of 2013  2014 in a delayed melt of freshwater lakes across the North American continent. In those years that correlated to increased melt in the HIGHEST Arctic but diminished extent and area losses overall.

2020 saw a delayed melt in North America as well although this ultimately mattered less to the final extent numbers. Will excessive melting in the High Arctic outdo the amount of ice now accumulating in the lower latitudes and Beaufort? I am unsure, but I do think this configuration supports substantial additional accretion of SWE, especially in North America.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on February 14, 2021, 08:33:46 PM
It is also interesting to note that the intense heat relative to normal across eastern Quebec as of late has been ENHANCING snowfall in this region. We have seen a year over year shift for early February to concentrate heat further in the High Arctic. I think this is an alarming prospect for the onset of spring and the CAB front.

Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 15, 2021, 05:44:28 PM
On 02/14/21, NH snow extent anomaly was +0.304 million km^2 according to Cryosphere Computing.  Slightly above average.  It's the first time I've seen it above average in quite a while.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 16, 2021, 06:22:18 PM
Certainly a spectacular amount of new snow especially in the lower 48, and a bit more especially in the NE today and tomorrow.

Relief in the form of warmth should be underway by Sunday from the south and west for the lower 48, but not for Canada.

I wonder how quickly the snow in the lower 48 will decline. It looks quite thick in many places.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on February 16, 2021, 07:53:58 PM
Between 1 foot and 2 feet of fresh snow in the Chicago metro area over the past 36 hours. The snowfall totals were heavier as you moved south. This on top of the foot on the ground. Finally sunny.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 17, 2021, 05:21:19 PM
BOOM!

On 02/16/21, NH snow extent anomaly was +2.339 million km^2 according to Cryosphere Computing.  Significantly above average.  That Texas snowstorm is really doing a doozy. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on February 17, 2021, 06:33:43 PM
I think this is the earliest in the season we have broken the SWE scale (OK, probably tomorrow).

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_swe.png)

And extent is the highest I can recall seeing, ever, in North America.

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_sce.png)

PS: I know my predictions of a looming +SWE spiral are met with skepticism especially when it comes to scenarios of rapid glaciation but I think the situation in Texas illustrates how rapidly things can fail in the face of unexpected change.

It is interesting to note that the resilience in the face of increasingly warm summertime temperatures actually appears greater vs. wintertime cold. Heatwaves have progressed gradually in most regions, and also generally do not come with problems for power grids beyond actual capacity being an issue.

When Arctic blasts occur, supply is hindered and capacity is also stretched.

I think what we have just witnessed across the US is a prelude to worse events in the next 5-10 years. Oklahoma City recorded its lowest temperature since 1899, records were smashed everywhere, and it isn't the heart of winter -- it is almost late February, insolation is almost two months past minimum.

What happens when we see an Arctic blast with a magnitude worse than this persist for a week, or two weeks? And the roads are clogged, and it is snowing or icing, and the power is out? This does not necessitate glaciation btw, this could just be a two week period of weather similar to what we just saw, which is hardly unfeasible given the new records we are now setting across parts of the US.

It must also be noted that one of the regions which this airmass passed over /originated has been cold since last summer, and that is the NW Rockies in Canada, where summertime temps were 2-3C below 1980-2010 normals. Similar to the Himalayas, or the mountains of NE Eurasia, a 2-3C drop in summertime temperatures here allows snowpack to survive or accrete for most of the summer, in fact these temperatures were not that far above the threshold for re-glaciation as they are co-located with very high elevations.

With so much thick ice now extant in the Beaufort, I suspect that this region could play host to anomalies that are even worse this summer, although I have been very wrong in the past re: Quebec et al. However, Quebec is isolated from multi-year sea ice (Baffin and Hudson do not retain it / although MYI flows do drift into Baffin and smatterings may survive one year to the next in the channels of the CAA, but that is kind of further north).

The NW Rockies are directly downwind of the huge mass of ice now pushing onto Alaska and the Yukon's northern shore. This ice mass may be pushed off at some point in spring or summer, or it may not be, but in either case, I would think that as the FYI and snowcover melt in the lower latitudes, this region could become an anchor of cold and snow and relatively -500MB anomalies during NHEM spring + summertime, which could lead to continued Arctic Blasts into the lower 48, which will also lead to continued degradation of the ATL ice front, as these blasts will ultimately transport oceanic heat from the Gulf of Mexico and NW NATL into Greenland and the Barentz / Kara / CAB.

We are already seeing this pattern setting in across most modeling, with scorching anomalies centering over the CAB and peripheral ATL front on a persistent basis. The snowcover situation developing in North America is likely to further exacerbate the situation especially with insolation rapidly increasing. For now, the anomalies are generating heat close to freezing, and a lot of snow as well I would guess -- but we are only a few weeks or less from 0C+ temperatures resulting from these heat pulses across the Highest Arctic.

Finally, I am very curious to see what happens in Quebec as a result of the current / future pattern. While it has been very warm relative to normal, it has still been below freezing, and this relative warmth has simultaneously allowed much greater moisture / snowfall vs. normal February conditions across Quebec. As +500MB anomalies likely continue gaining prominence in the Highest Arctic as we head into spring, and the lowest latitudes melt out re: snowfall, -500MB anomalies are likely to concentrate in areas that retain +SWE, which probably includes Quebec. I could see the pattern shifting towards a very cold Canada in March, April, May, and possibly extending into June and July for the regions most prone to retaining snowpack.

This would severely blunt melting momentum for the Beaufort, Hudson, and CAA, while -- for reasons stated above -- contributing to melt momentum along the Atlantic oceanic periphery of the CAB.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: interstitial on February 17, 2021, 09:06:04 PM
So should natural gas plants in Texas and southern US sue themselves for weatherization of their plants? ;D
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on February 17, 2021, 09:25:45 PM
bbr - reglaciation is not to be discussed here. Off limits.
Regardless, snow blasts in winter are expected to increase, with the current event being a nice example of an extreme outlier.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 17, 2021, 10:56:25 PM
LOL, NH snow extent anomaly has been negative for almost the entire winter, and the moment we get a momentary positive anomaly bbr is back on here.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on February 18, 2021, 12:34:18 AM
LOL, NH snow extent anomaly has been negative for almost the entire winter, and the moment we get a momentary positive anomaly bbr is back on here.

I, for one, would be happy to see more snow survive the summers in the Rockies where glaciers have been retreating for decades.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: The Walrus on February 18, 2021, 03:31:39 AM
The current U.S. snow cover is the highest ever mapped, according to NOAA.  However, the database only tracks to 2003.

https://weather.com/storms/winter/news/2021-02-17-snow-cover-united-states-most-widespread-since-2003
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 18, 2021, 02:36:17 PM
I, for one, would be happy to see more snow survive the summers.....
The US Declaration of Independence states
Quote
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.

You have the right to seek happiness, but not necessarily to find it.

Relief from snow for the Lower 48 starts Saturday and spreads North to the Canadian border by Tuesday.

But no relief for Canada.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: be cause on February 18, 2021, 04:30:49 PM
my mother's uncle admitted defeat and returned with his family from central Canada 110 years ago .. 'too cold to bear' he wrote home to his mother . His shame made him volunteer for war and he died in 1916 on the Belgian / French border . b.c.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Tor Bejnar on February 18, 2021, 04:39:17 PM
Quote
But no relief for Canada.
It looks like it's pleasant in Nova Scotia.  (It was part of "Canada" when I visited as a kid, anyway.)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: bbr2315 on February 18, 2021, 05:36:01 PM
We have officially broken the SWE scale in North America, crossing the 1,400 KM^3 mark!

(https://ccin.ca/home/sites/default/files/snow/snow_tracker/na_swe.png)

It looks like we are roughly matching the trajectory in 2018-19.

I wonder how Newfoundland and Nova Scotia's pack will evolve. I could see an early start to spring, or, will the open water allow greater moisture, combining with continental airmasses for major snowfalls in spite of the lack of sea ice in the St. Lawrence and around Newfoundland?

It will be interesting to see the push-pull evolve this season in this region. With all the warmth in the NW NATL, there is certainly a case for an early melt of the low latitude snows in the US / Canada, but will the high latitude +500MB blocking turn the periphery of the Bermuda High into a factory for snow? We shall see.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: The Walrus on February 18, 2021, 07:46:02 PM
Quote
But no relief for Canada.
It looks like it's pleasant in Nova Scotia.  (It was part of "Canada" when I visited as a kid, anyway.)

A temporary situation.  The current winter storm is expected to exit the continent right over top of them, bringing cold and snow.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: HapHazard on February 18, 2021, 07:57:40 PM
It's fine here, too (middle of nowhere BC) - this is the lowest amount of snow we've had at this time of year in the 15 years or so that I've been living here.

Also, LOL Comradez - I had the same reaction to that post...  ::)  :o  ;D
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 18, 2021, 08:25:25 PM
It's fine here, too (middle of nowhere BC) - this is the lowest amount of snow we've had at this time of year in the 15 years or so that I've been living here.

Also, LOL Comradez - I had the same reaction to that post...  ::)  :o  ;D
Most of Canada has been pretty dry during this cold event - but when it gets too cold I thought that stopped snow from falling, and the front of the Polar Vortex has mostly been wandering across the Lower 48?
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Alphabet Hotel on February 18, 2021, 08:57:20 PM
We have officially broken the SWE scale in North America, crossing the 1,400 KM^3 mark!


I think much of that is due to snow falling in southerly places where it doesn't usually happen, though. It should melt soon.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: kassy on February 18, 2021, 10:21:36 PM
Not often but occasionally:

The more you read about events in Texas, the more you realise how avoidable the problem was.

Three reports have come to light  in 1989, 2003 and 2011 after previous events where severe cold brought the Texas grid to it's knees.

The findings are the same in all of them, instrumentation was not designed, nor protected from the conditions experienced.

I really hope this time lessons are learnt

https://twitter.com/kidstatic/status/1361914812305985538?s=20
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 23, 2021, 11:51:43 AM
What goes up - goes down, especially at lower latitudes in latish February.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on February 24, 2021, 02:20:16 AM
Not often but occasionally:

The more you read about events in Texas, the more you realise how avoidable the problem was.

Three reports have come to light  in 1989, 2003 and 2011 after previous events where severe cold brought the Texas grid to it's knees.

The findings are the same in all of them, instrumentation was not designed, nor protected from the conditions experienced.

I really hope this time lessons are learnt

https://twitter.com/kidstatic/status/1361914812305985538?s=20

It's Texas. They're not big on larnin' down there.  ;)
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: The Walrus on February 24, 2021, 03:47:33 AM
Not often but occasionally:

The more you read about events in Texas, the more you realise how avoidable the problem was.

Three reports have come to light  in 1989, 2003 and 2011 after previous events where severe cold brought the Texas grid to it's knees.

The findings are the same in all of them, instrumentation was not designed, nor protected from the conditions experienced.

I really hope this time lessons are learnt

https://twitter.com/kidstatic/status/1361914812305985538?s=20

It's Texas. They're not big on larnin' down there.  ;)

It is not just Texas.  In 2014, Atlanta received 2.5” of snow and the city was brought to a standstill, with estimates of a million people stuck on the highways.  The city did not fare much better during the “blizzard” of 2011.  As far as bad timing goes, the ice storm of 2000 struck during the super bowl. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on February 24, 2021, 02:13:45 PM
What goes up - goes down, especially at lower latitudes in latish February.

Looks like this melt will continue some more (but not so much in Canada)

click images to enlarge
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on February 24, 2021, 04:35:11 PM
Amazing how fast the snow is melting in Chicago. We had nearly 2 feet on the ground. It's dropped by a foot in the past week. Highs in the low 40's through the first week in March should wipe it out.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 26, 2021, 08:20:12 PM
According to Cryosphere Computing, NH snow cover extent now (2/25) has an anomaly of -0.567 million km^2. 

Above-average temperatures are forecasted over the next 10 days for eastern North America, Europe, and Northern China. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on February 28, 2021, 09:56:23 PM
According to Cryosphere Computing, NH snow cover extent now (2/27) has an anomaly of -0.831 million km^2.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on March 01, 2021, 11:30:57 AM
North America

While the snow at lower latitudes from the big storm has melted (i.e. mostly in the lower 48) , snow water equivalent has not gone down. That means more snow at high latitudes , i.e. mostly Canada, and average depth also increased.

Eurasia
Gradual reduction in snow cover extent and no reduction in snow water equivalent.

Click to enlarge attached images
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on March 01, 2021, 04:30:41 PM
According to Cryosphere Computing, NH snow cover extent now (2/28) has a significant anomaly of -1.491 million km^2.

Negative anomalies are now present in all 3 regions (North America, Europe, and Asia).  Very warm temperatures forecasted for the next 10 days for the Great Plains, Europe, and Central Asia.  Will this albedo anomaly end up being a bootstrap for an ahead-of-schedule snow melt season (and thus also a sea ice melt season)?
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on March 02, 2021, 04:12:09 PM
According to Cryosphere Computing, NH snow cover extent now (3/1) has an anomaly of -1.684 million km^2.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on March 03, 2021, 11:33:18 AM
The contrast between falling Snow Cover Extent (SCE) and increasing Snow Water Equivalent (SWE) continues to grow.

Once again the question is whether that thicker snow at higher latitudes will slow down snow melt significantly.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on March 04, 2021, 03:54:17 PM
According to Cryosphere Computing, NH snow cover extent now (3/3) has an anomaly of -1.784 million km^2. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Shared Humanity on March 05, 2021, 02:04:09 AM
The contrast between falling Snow Cover Extent (SCE) and increasing Snow Water Equivalent (SWE) continues to grow.

Once again the question is whether that thicker snow at higher latitudes will slow down snow melt significantly.

Don't know the answer to that question but I do think the trends towards higher SWE (mainly in the northern latitudes) and lower SCE (due to less precipitation as snow in the lower latitudes) is here for good.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: oren on March 05, 2021, 02:21:45 AM
I agree, and also think higher SWE in winter will not be making it into spring, as a general trend.
My past "research" into individual weather stations did not show much correlation of higher snow thickness in winter with a later melt-out date.
Certainly the inconvenience and potential spring flooding resulting from more winter snow are here to stay in many northern places.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on March 05, 2021, 03:23:12 PM
According to Cryosphere Computing, NH snow cover extent now (3/4) has a quite substantial anomaly of -2.522 million km^2.

The weather looks to be exceedingly warm over the U.S. and northern China over the next 10-14 days.  Last year in Missouri we had several cold snaps that kept trees and bushes from budding until mid-April.  We may end up being a month earlier this year.  It is not forecasted to drop below freezing even once in that upcoming timeframe here. 
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: Comradez on March 06, 2021, 04:26:12 PM
According to Cryosphere Computing, NH snow cover extent now (3/5) has a whopping anomaly of -3.118 million km^2.
Title: Re: Northern Hemisphere Winter 2020-2021 Snowcover / Misc Obs
Post by: gerontocrat on March 07, 2021, 01:47:58 PM
https://ccin.ca/ccw/snow/current

The images from Environment Canada show that as far as Snow Cover Extent (SCE) is concerned, the snowmelt season is underway, at least at lower latitudes.

It may be that in North America the Snow Water Equivalent (SWE i.e. mass) this is also in decline. But in Eurasia SWE is still increasing strongly.