Tropical cyclone, Hurricane Season 2023

[KiwiGriff]

NZ just got hammered by ex tropical cyclone Hale. This storm will go down in history besides Bola and Giselle as  major weather events for NZ . First world problems. I am presently trapped at the beach house with the highways north and south closed due to slips and flooding.
Forecasts suggest we may be in  line for another cyclone  next week.

[Alexander555]

1000 mm of rain in a few days. https://watchers.news/2023/01/25/tropical-cyclone-cheneso-rapidly-intensifies-after-leaving-a-trail-of-death-and-destruction-in-madagascar/

[KiwiGriff]

Here we go again.
Northland and Auckland had the ex tropical cyclone above then an extreme  rainfall event .
were almost 400mm of rain in a day was recorded in parts of Auckland.

Another  cyclone is lining us up for round three.
 
Ex Cyclone Gabrielle is forecast to hit Monday. Tracking is not fully resolved but most models are predicting the worse case scenario.

[Richard Rathbone]

This is the subject of the current eye on the storm post.

https://yaleclimateconnections.org/2023/02/auckland-just-had-its-wettest-month-in-over-170-years-and-more-rain-is-on-the-way/

Climate change is exacerbating the wet setup, as a freight train of rainmaking systems from the tropical western Pacific draws on unusually high sea surface temperatures (up to six degrees Celsius or 11 degrees Fahrenheit above average near the South Island) associated with a marine heat wave. Intensified short-term rains and warming oceans are two of the most clearly established effects of a human-warmed planet.

Auckland had already racked up one of its wettest months in 170 years of record-keeping before an especially intense round of rain on Jan. 28 triggered particularly severe flooding. The month’s final total of 539 millimeters (21.22 inches) was more than 25% higher than any other month going back to 1853, including the old record of 420 mm (16.54 inches) set in February 1869, according to NIWA, New Zealand’s National Institute of Water and Atmospheric Research/Taihoro Nukarangi.

Gabrielle is predicted to head on a straightforward southeast track over the next several days, peaking as a high-end category 1 hurricane with 90 mph winds on Friday morning (U.S. EST). By late in the weekend, Gabrielle should hook southward just as it nears the North Island, likely going through post-tropical transition around this time, and Gabrielle may be subtropical or extratropical when it makes its closest approach to New Zealand. Tropical cyclones are uncommon in New Zealand; NOAA’s historical hurricane database shows only two hurricane-force storms have ever hit the island, Tropical Cyclone Gisele (1968) and Tropical Cyclone Alison (1975).

Regardless of how the storm is classified, the predicted motion would allow Gabrielle’s clockwise circulation to fling a large field of deep tropical moisture across the North Island. Ensemble output from the GFS model (GEFS) indicates that the Auckland area could easily pick up four inches or more of rainfall on Sunday and Monday, with even heavier amounts possible across east-facing slopes. Falling on saturated soils, the heavy rain could lead to serious flooding. High winds from Gabrielle could bring down trees and power lines.

[Jim Hunt]

Cyclone Freddy is currently heading across the Indian Ocean towards Madagascar:

[Richard Rathbone]

Freddy is the first cat 5 of 2023 and likely to still be a major when it hits Madadascar.
Could break ACE records.

https://yaleclimateconnections.org/2023/02/first-cat-5-of-2023-cyclone-freddy-weakens-to-cat-4-and-heads-toward-madagascar/

According to the Joint Typhoon Warning Center, Freddy peaked with 165 mph winds at 0Z Feb. 16 (7 p.m. EST Feb. 15). According to NOAA’s historical hurricane tracks website, this makes Freddy one of only five category 5 storms ever recorded in February on Earth. The only February storm stronger than Freddy (by wind speed) was Tropical Cyclone Winston of 2016, which peaked with 180 mph winds near Fiji on Feb. 20, 2016.

Freddy will be an unusually long-lived tropical cyclone for the Indian Ocean. Freddy was named Feb. 7 off the coast of northwestern Australia and has already generated about 35 units of accumulated cyclone energy, or ACE, a measure of cyclone strength over time. According to Dr. Phil Klotzabach of Colorado State, Freddy looks likely to eclipse the Southern Hemisphere single-storm record for ACE of about 53 currently held by Cyclone Fantala of 2016. According to Colorado State, the southern Indian Ocean is already 45% above average for ACE for the 2022-23 season, mostly because of Cyclone Darian of December (42.5 ACE units) and now Freddy.

Freddy represents a significant flood threat for Madagascar. Soils are saturated in central parts of the island from the impact of Cyclone Cheneso, which stalled off the west coast of the island and brought torrential rains Jan. 19-21 that killed 33 people, left 20 missing, and made 34,000 people homeless.

[vox_mundi]

Tropical Cyclone Freddy from the ISS...

latest update: sustained 10 minute average wind 136mph (gusts are estimated to be 220mph)...pressure at 931mb...forecast to hit Madagascar on Tuesday and Mozambique later in the week.

https://twitter.com/ISSAboveYou/status/1626652187488313344

[gerontocrat]

Tropical Cyclone Freddy: Forecast from the US Navy https://www.metoc.navy.mil/jtwc/jtwc.html says 105 knots at landfall.

WDXS31 PGTW 191500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 11S (FREDDY) WARNING
NR 034//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 17.4S 64.1E
   INITIAL INTENSITY: 130 KTS
   GEOGRAPHIC REFERENCE: 419 NM EAST-NORTHEAST OF PORT LOUIS,
MAURITIU
   MOVEMENT PAST 6 HOURS: WEST-SOUTHWESTWARD AT 16 KTS
   SIGNIFICANT WAVE HEIGHT: 46 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A FAIRLY
SYMMETRICAL SYSTEM WITH RELATIVELY RAGGED BANDING IN THE NORTHERN
AND SOUTHERN PERIPHERIES. TC FREDDY IS SHOWING SIGNS OF A SLOWLY
EXPANDING EYE WHICH INDICATES A WEAKENING TREND. A 190523Z ASCAT-B
IMAGE SHOWS THE 34, 50, AND 64 KNOT WIND RADII TO BE IN A SOMEWHAT
BALANCED DISTRIBUTION AROUND THE LOW LEVEL CIRCULATION CENTER (LLCC).
ENVIRONMENTAL ANALYSIS INDICATES TC 11S TO BE IN FAVORABLE CONDITIONS
FOR CONTINUAL TROPICAL DEVELOPMENT. THESE CONDITIONS ARE
CHARACTERIZED BY CONSISTENT WESTERLY OUTFLOW ALOFT, LOW (5-10 KTS)
VERTICAL WIND SHEAR (VWS), A VERY STRONG 850 MB VORTICITY SIGNATURE,
AND WARM (27-28 C) SEA SURFACE TEMPERATURES (SST). THE INITIAL
POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE ABOVE MENTIONED
MSI AND SCATTEROMETRY IMAGES. THE INITIAL INTENSITY OF 130 KTS IS
ASSESSED WITH MEDIUM CONFIDENCE SET SLIGHTLY HIGHER THAN MULTI-AGENCY
AND AUTOMATED DVORAK ESTIMATES.

INITIAL WIND RADII BASIS: SCATTEROMETER DATA

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) TO THE
SOUTHEAST

AGENCY DVORAK AND AUTOMATED FIXES:
   PGTW: T6.5 - 127 KTS
   KNES: T6.5 - 127 KTS
   DEMS: T6.5 - 127 KTS
   FMEE: T6.5 - 127 KTS
   CIMSS SATCON: 122 KTS AT 190859Z
   CIMSS ADT: 125 KTS AT 191230Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 5-10 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: MODERATE WESTWARD

ANALYSIS CONFIDENCE:
   INITIAL POSITION: HIGH
   INITIAL INTENSITY: MEDIUM
   INITIAL WIND RADII: HIGH

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TC FREDDY CONTINUES ITS WEST-SOUTHWESTWARD
TRACK AS IT TRANSITS THE NORTHEASTERN PERIPHERY OF THE STR TO THE
SOUTHEAST. COPIOUS AMOUNTS OF DRY AIR WILL CONTINUE TO SURROUND THE
SYSTEM, HOWEVER, TC FREDDY WILL STAY COCOONED IN ITS OWN MOISTURE
POCKET THROUGHOUT ITS FORECAST TRACK. THE SYSTEM WILL CONTINUE ITS
WEST-SOUTHWESTWARD TRAJECTORY AND GRADUALLY DECREASE IN INTENSITY
TO 105 KNOTS AS IT MAKES ITS APPROACH TO THE EAST COAST OF
MADAGASCAR SHORTLY AFTER TAU 48. TC 11S IS FORECAST TO FURTHER
DECREASE IN INTENSITY TO 45 KNOTS BY TAU 72 AS IT TRANSITS ACROSS
THE MOUNTAINOUS TERRAIN OF SOUTHERN MADAGASCAR. BY TAU 96, THE SYSTEM
WILL BE IN ANOTHER FAVORABLE ENVIRONMENT OVER THE MOZAMBIQUE CHANNEL
AND RE-INTENSIFY TO 55 KNOTS AS A RESULT. BY TAU 120, TC FREDDY WILL
APPROACH THE MOZAMBIQUE COAST SOUTH OF BEIRA AND DECREASE TO 45 KNOTS
DUE TO LAND INTERACTION.

MODEL DISCUSSION: THE JTWC MODEL TRACK CONSENSUS REMAINS IN TIGHT
AGREEMENT WITH A GRADUAL SPREAD TO 70 NM BY TAU 48. AFTERWARDS, THE
SPREAD INCREASES TO 240 NM BY TAU 120 AS THE MEMBERS DISAGREE WITH
THE TRAJECTORY OVER THE MOZAMBIQUE CHANNEL. GFS DETERMINISTIC AND
ENSEMBLE GUIDANCE TAKES TC 11S ON A MORE WEST-NORTHWESTWARD TRACK
WHILE CROSSING OVER THE MOZAMBIQUE CHANNEL, WHEREAS THE OTHER
MEMBERS KEEP THE SYSTEM ON A WEST-SOUTHWESTWARD TRACK. THE FORECAST
TRACK IS SET SLIGHTLY TO THE RIGHT OF CONSENSUS AFTER TAU 72 TO
ACCOUNT FOR THE OFFSET OF THE GFS GUIDANCE. BECAUSE OF THIS, THE
JTWC FORECAST TRACK IS PLACED WITH HIGH CONFIDENCE UP TO TAU 72,
THEN MEDIUM CONFIDENCE THEREAFTER. THE INTENSITY GUIDANCE IS ALSO
IN GOOD AGREEMENT WITH THE EXCEPTION OF GFS WHICH DECREASES THE
INTENSITY WELL BEYOND THE OTHER CONSENSUS MEMBERS. THE JTWC
INTENSITY FORECAST IS SET WITH MEDIUM CONFIDENCE.

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: HIGH
   TRACK 72-120 HR: MEDIUM
   INTENSITY 0 - 72 HR: MEDIUM
   INTENSITY 72-120 HR: MEDIUM//
NNNN

click image to enlarge & maximise for full size

[kassy]

Cyclone Gabrielle: Rebuilding cost on par with Christchurch quake - NZ

New Zealand has said rebuilding after Cyclone Gabrielle will cost billions of dollars, on par with the Christchurch earthquake from 12 years ago.

Gabrielle brought widespread flooding to the North Island in mid-February, damaging roads and bridges.

At least 11 people have died so far and thousands are still uncontactable.

"It's going to be the biggest weather event this century, with a billion dollar price tag," Finance Minister Grant Robertson said.

Mr Robertson told TVNZ over the weekend that the government would first attend to survivors' most urgent needs - food, shelter, electricity and communications.

"We have a long journey ahead of us to rebuild after this disaster, but we have the resources to do it, and we have the will to do it," Mr Robertson said.

Farmers lost entire harvests and herds to the floods and authorities are still determining how much of it will be covered by insurance, said the minister, who is in charge of rebuilding efforts.

On Monday, Prime Minister Chris Hipkins announced an additional NZ$250m (£129.6m) to fix damaged roads and a NZ$50m (£25.9m)-support package to give immediate relief for businesses.

...

Mr Robertson blamed the extent of the damage inflicted by Gabrielle on New Zealand's failure to build infrastructure that's resilient to climate change, adding that the current approach to adapt "has not been sufficiently robust".

...

Many of the roads damaged by Gabrielle are still closed. Tanker trucks cannot collect milk, some logging is suspended and meat processing is scaled down, Reuters reported.

The cyclone also disrupted picking in apple and pear farms, where annual production is valued at NZ$1 billion. Many of these areas are still inaccessible.

Farm damage could push food prices higher, adding pressure to inflation that's already running at a near three-decade high of 7.2%.

https://www.bbc.com/news/world-asia-64672099

It´s not really clear what infrastructure could be build against this sort of storm...

[gerontocrat]

Freddy is a dangerous beast. 110 knots at Madagascar landfall is not good.

click attached image to enlarge then click maximise for full size

WDXS31 PGTW 200300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 11S (FREDDY) WARNING NR
035//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 18.1S 60.7E
   INITIAL INTENSITY: 130 KTS
   GEOGRAPHIC REFERENCE: 227 NM EAST-NORTHEAST OF PORT LOUIS,
MAURITIUS
   MOVEMENT PAST 6 HOURS: WEST-SOUTHWESTWARD AT 17 KTS
   SIGNIFICANT WAVE HEIGHT: 46 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
AFTER PEAKING AT 140 KNOTS OR POTENTIAL A BIT HIGHER, FOR AN
IMPRESSIVE FOURTH TIME IN ITS LIFE, TC 11S (FREDDY) HAS WEAKENED
CONSIDERABLY OVER THE PAST 12 HOURS, AND IN PARTICULARLY IN THE
LAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY
AND CIMSS TC DIURNAL CLOCK CLOUD TOP CHANGE PRODUCTS DEPICT
SIGNIFICANT WARMING OF THE CLOUD TOPS, PARTICULARLY ACROSS THE
SOUTHERN HEMISPHERE OF THE STORM. AT THE SAME TIME, THE EYE
TEMPERATURE HAS STARTED TO COOL SLIGHTLY, AFTER HAVING PEAKED
NEAR +20C. THE FACT THAT THESE CHANGES ARE OCCURRING THROUGH THE
DIURNAL CONVECTIVE MAXIMUM IS INDICATIVE OF OTHER PROCESSES
INTERFERING WITH THE MAINTENANCE OF THE CORE OF THE SYSTEM. A
192313Z SSMIS 91GHZ IMAGE SHOWS A STATIONARY BANDING COMPLEX (SBC)
DEVELOPING ACROSS THE SOUTHERN HEMISPHERE OF THE SYSTEM, LIKELY
CONNECTING TO THE INNER EYEWALL ON THE NORTHWEST SIDE. THIS COULD
POTENTIALLY MARK THE BEGINNING OF THE LONG-ANTICIPATED EYEWALL
REPLACEMENT CYCLE (EWRC), AND THE FULL-MODEL M-PERC SHOWS AN
INCREASING LIKELIHOOD OF EWRC IN THE NEXT 12 HOURS OR SO. EVEN
WITHOUT AN EWRC, THE PRESENCE OF SBC IS USHERING IN SOME DRY
MID-LEVEL AIR INTO THE CORE AND DISRUPTING THE ENERGY INFLOW,
LEADING TO THE WEAKENING TREND SEEN OVER THE PAST 12 HOURS. THE
INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED ON THE 25NM
EYE IN THE EIR AND MICROWAVE IMAGE AND ON THE FIRST HINTS OF THE
EYE ON THE MAURITIUS RADAR. THE INITIAL INTENSITY IS ASSESSED WITH
HIGH CONFIDENCE BASED ON A BLEND OF SUBJECTIVE AND OBJECTIVE AGENCY
DVORAK CURRENT INTENSITY ESTIMATES, HEDGED CLOSE TO THE CIMSS DEEP
MICRONET AND OPEN-AIIR INTENSITY ESTIMATES. OVERALL, THE
ENVIRONMENT REMAINS FAVORABLE, WITH MINIMAL SHEAR, WARM (THOUGH
ABOUT A HALF DEGREE COOLER THAN 12 HOURS AGO) AND STRONG RADIAL
OUTFLOW WITH THE ADDITION OF A POLEWARD OUTFLOW CHANNEL.

INITIAL WIND RADII BASIS: PERSISTENCE

CURRENT STEERING MECHANISM: NORTHERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) TO THE SOUTH.

AGENCY DVORAK AND AUTOMATED FIXES:
   PGTW: T7.0 - 140 KTS
   KNES: T6.5 - 127 KTS
   DEMS: T7.0 - 140 KTS
   FMEE: T6.5 - 127 KTS
   FIMP: T7.0 - 140 KTS
   CIMSS SATCON: 137 KTS AT 192058Z
   CIMSS ADT: 127 KTS AT 200000Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 0-5 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: STRONG RADIAL
   OTHER FACTORS: SBC, POSSIBLE EWRC AND MID-LEVEL DRY AIR
ENTRAINMENT

ANALYSIS CONFIDENCE:
   INITIAL POSITION: HIGH
   INITIAL INTENSITY: HIGH
   INITIAL WIND RADII: LOW

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: NO MAJOR CHANGES IN THE TRACK ARE ANTICIPATED,
AS THE SYSTEM TRAVERSES WEST-SOUTHWESTWARD ALONG THE NORTHERN SIDE
OF STRONG STR TO THE SOUTH. TC 11S IS FORECAST TO PASS ABOUT
60-95NM NORTH OF BOTH MAURITIUS AND LA REUNION WITHIN THE NEXT 24
HOURS BEFORE MAKING LANDFALL ALONG THE SOUTH-CENTRAL COAST OF
MADAGASCAR AROUND TAU 40. WHILE OVERALL CONDITIONS ARE FORECAST TO
REMAIN FAVORABLE THROUGH LANDFALL, MODEST WEAKENING IS FORECAST DUE
TO AN EXPECTED EWRC. ASSUMING THE EWRC STARTS SOON, IT SHOULD BE
WRAPPED UP AROUND TAU 24, LEAVING BEHIND A LARGER SYSTEM IN
GENERAL, WITH A LARGER EYE. CURRENT NCODA AND SATELLITE ANALYSIS
REVEALS A WARM POOL, WITH SSTS APPROACHING 29C AND OHC VALUES OVER
40 KJ PER CM2, SITUATED ABOUT 70-100NM OFF THE EAST COAST OF
MADAGASCAR. TC 11S IS FORECAST TO TRACK DIRECTLY OVER THIS POOL OF
WARMER WATERS AS IT APPROACHES LANDFALL. THE FORECAST THUS CALLS
FOR AN INTENSITY OF 110 KNOTS AT TAU 36, WEAKENING TO 90 KNOTS
SHORTLY AFTER LANDFALL. IN BETWEEN THESE FORECAST POINTS, THE
SYSTEM MAY ACTUALLY REACH A HIGHER INTENSITY AS IT CROSSES THE WARM
POOL, SLAMMING INTO MADAGASCAR AS A SIGNIFICANT TC. AS THE SYSTEM
CROSSES THE ROUGH TERRAIN OF MADAGASCAR IT WILL WEAKEN DRASTICALLY,
LOSING ITS LOW-LEVEL STRUCTURE, BUT MAINTAINING THE MID-LEVEL
SIGNATURE. ONCE EXITING THE ISLAND AND EMERGING INTO THE MOZAMBIQUE
CHANNEL, TC 11S WILL TURN TO A MORE WESTWARD TO WEST-NORTHWESTWARD
TRACK AS THE STEERING MECHANISM SHIFTS TO A BUILDING STR OVER SOUTH
AFRICA. ANOTHER ROUND OF INTENSIFICATION, AND POTENTIALLY RAPID
INTENSIFICATION IS POSSIBLE IN THE CHANNEL AS THE SYSTEM TAPS INTO
A VERY FAVORABLE ENVIRONMENT, WITH SSTS OVER 29C, LOW SHEAR AND
STRONG OUTFLOW ALOFT. THE ONLY HINDRANCE WILL BE THE AMOUNT OF
TIME IT STAYS OVER WATER BEFORE MAKING LANDFALL ALONG THE CENTRAL
COAST OF MOZAMBIQUE.

MODEL DISCUSSION: TRACK GUIDANCE THROUGH LANDFALL IS IN VERY TIGHT
AGREEMENT, THOUGH THE NAVGEM AND UKMET ENSEMBLE MEAN TRACKERS HAVE
STARTED TO DIVERGE SOUTHWARD. THIS IS A KNOWN BIAS WITH THESE
MODELS AND THEY HAVE BEEN DISCARDED FROM THE CONSENSUS.
UNSURPRISINGLY, MODELS BEGIN TO DIVERGE AFTER LANDFALL, WITH TWO
DISTINCT CAMPS EMERGING BY TAU 72. THE NORTHERN GROUP CONSISTING OF
THE US MODELS (GFS, HWRF, COAMPS, AND GEFS) TRACK THE SYSTEM
WEST-NORTHWESTWARD AFTER TAU 72. THE SOUTHERN GROUP OF THE EUROPEAN
MODELS (ECMWF, UKMET, THEIR ENSEMBLES AND THE NAVGEM) KEEP A RATHER
FLAT WESTWARD TRAJECTORY THROUGH TAU 120, WITH ABOUT 120NM BETWEEN
THE TWO GROUPS. THE JTWC FORECAST STICKS WITH THE NORTHERN GROUP,
THOUGH CONFIDENCE DECREASES TO MEDIUM IN THE LONG-TERM DUE TO THE
INCREASED MODEL SPREAD. INTENSITY GUIDANCE IS ALSO IN GOOD
AGREEMENT, WITH ALL AVAILABLE GUIDANCE INDICATING WEAKENING, SOME
DOWN TO AS LOW AS 100 KNOTS, THROUGH TAU 24, FOLLOWED BY A
FLATTENING OF THE TREND THROUGH LANDFALL. THE MODELS CONVERGE
AROUND A 40-50 KNOT SYSTEM EMERGING INTO THE CHANNEL AROUND TAU 60,
FOLLOWED BY VARIED AMOUNTS OF INTENSIFICATION. THE CTCX KEEPS THE
SYSTEM IN THE CHANNEL LONGER AND PEAKS AT 95 KNOTS, WHILE THE HWRF
AND COTC PEAK NEAR 65 KNOTS. THE JTWC FORECAST IS CONSISTENT WITH
THE COAMPS-TC TRACKER THROUGH THE ENTIRE FORECAST.

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: HIGH
   TRACK 72-120 HR: MEDIUM
   INTENSITY 0 - 72 HR: MEDIUM
   INTENSITY 72-120 HR: LOW//
NNNN

[Jim Hunt]

Freddy making landfall in infrared.

Via: https://cimss.ssec.wisc.edu/satellite-blog/

[Click to animate/enlarge. 11 Mb]

[Richard Rathbone]

https://yaleclimateconnections.org/2023/02/category-3-cyclone-freddy-hits-madagascar/

Record breaking by Freddy

Freddy is an unusually long-lived and powerful tropical cyclone for the Indian Ocean. Freddy was named Feb. 7 off the coast of northwestern Australia and has already generated about 66 units of accumulated cyclone energy, or ACE, a measure of cyclone strength over time, according to Dr. Phil Klotzbach of Colorado State. This breaks the previous Southern Hemisphere single-storm record for ACE of 53 formerly held by Cyclone Fantala of 2016. Only two Atlantic hurricanes have had a higher lifetime ACE index than Freddy: Hurricane Three of 1899 (ACE of 73.6) and Hurricane Ivan of 2004 (ACE of 70.4). The highest ACE for a single tropical cyclone globally is 82, for Hurricane/Typhoon Ioke in 2006. Freddy will not break this record; the current Joint Typhoon Warning Center forecast calls for Freddy to gain another 3-4 ACE units before its demise, giving it a lifetime ACE near 70.

Freddy also did something no other Southern Hemisphere tropical cyclone has done: undergo four separate rounds of rapid intensification

Lots of rain coming both on Madagascar and its forecast to stall when it reaches Africa so there could be major rain there too.

[Jim Hunt]

Via: https://twitter.com/metofficestorms/status/1629065995296841729

Severe Tropical Storm Freddy is making landfall over Mozambique close to the town of Vilankulos. It will become slow-moving as it weakens and is expected to produce over 500 mm rain during the next few days with potential for severe flooding.

[oren]

I think the proper thread is "Tropical cyclone, Hurricane Season 2023"

This post moved from the 2022 thread with what is now reply 1 above. Kassy.

[gerontocrat]

Cyclone Judy is continuing on a North to South track ideal for hitting almost all the islands of the archipelago that comprise Vanuatu with sustained winds from 85 to 105 knots.

Yet another cyclone that has experienced Rapid Intensification.

click image to enlarge, click again for full size

https://www.stuff.co.nz/pou-tiaki/131368454/tropical-cyclone-judy-intensifies-to-category-4-lashes-vanuatu
Tropical Cyclone Judy intensifies to category 4, lashes Vanuatu

Tropical Cyclone Judy has strengthened to a category 4 storm in Vanuatu late Wednesday, with winds of up to 200kph, the Fiji MetService is reporting.

And it is forecast to intensify to a category 5 – the highest level – on Thursday.

Large waves, heavy rain and gale- to hurricane-force winds lashed the Pacific nation since making landfall on Wednesday morning.

Vanuatu emergency officials said a red alert remains for northern Vanuatu including the capital Port Vila.

Residents in Vanuatu were hunkering down as as the cyclone wreaked havoc on the Pacific nation.

On Tuesday night, Judy had strengthened to a category 3 storm, causing high winds, dangerous seas, and heavy, flooding rain across Vanuatu.

“At 6pm today local time, TC Judy will attain category 4 strength over Tanna Island. It will be at cat 4 strength for 12 hours,” Fiji MetService said.

Judy is expected to remain well northeast of New Zealand and currently poses no major threat to Aotearoa and Vanuatu’s neighbours, Fiji and the Solomon Islands. However, both countries have been experiencing heavy rain due to the cyclone.

MetService said another cyclone may impact Vanuatu on Friday or Saturday.

For Vila residents Sam and Kayla Joachime, getting hit by one cyclone was bad enough but “knowing there are more to come is very stressful”.

[gerontocrat]

Vanuatu

Why have just one cyclone, when you can have two in two days ? And an earthquake inbetween.

https://www.bbc.co.uk/news/world-asia-64832870
Vanuatu: Pacific nation reels from twin cyclones and earthquake

The Pacific nation of Vanuatu has declared a state of emergency as it reels from an earthquake and two cyclones in as many days.

The 6.5 magnitude quake struck on Friday, a day after category four Cyclone Judy swept through the islands.

The storm caused widespread damage and flooding across the country. No casualties have been reported yet.

A category three storm, Cyclone Kevin, arrived on Friday, bringing destructive winds of up to 130km/h (81mph).

Hundreds of people had fled to evacuation centres in the capital Port Vila ahead of the second cyclone.

"We are a resilient people. We will get through this," Vanuatu's Prime Minister Ishmael Kalsakau told broadcaster RNZ Pacific on Friday.

Aid workers have described the situation as unprecedented.

"It's crazy, Vanuatu is used to natural disasters, but I think this is the first time it has had two cyclones back to back," said UNICEF's Eric Durpaire, according to AFP news agency.

He said he had heard reports that Wednesday's storm had ripped off the roof of an infants ward in Vanuatu Central Hospital.

Cyclone Judy flooded roads and uprooted trees after it cut a north to south path through the island.

The Pacific state has already requested help from neighbours. Australia - a three hour plane ride away - said on Friday it would send water and medical supplies and a team of workers to assess the damage. New Zealand has also pledged assistance.

Vanuatu, a country of about 300,000 people, has been ranked the nation most prone to natural disasters by the United Nations.

It regularly experiences cyclones, and this week's disasters came as Vanuatu's UN mission secured a historic motion to ask the International Court of Justice to define what legal responsibility countries have for the changing climate and its impacts.

Vanuatu said securing the support of 105 other nations - including the UK, Canada and Australia - to co-sponsor the motion had been a "herculean diplomatic effort". China and the US - two of the world's biggest carbon emitters - did not sign on.

Pacific countries like Vanuatu have been at the forefront of legal climate change battles in recent years as rising sea levels, ocean acidification and the increased frequency and severity of natural disasters have been felt acutely across the region.

[vox_mundi]

Cyclone Freddy Kills Four In 'Rare' Return to Madagascar
https://phys.org/news/2023-03-cyclone-freddy-rare-madagascar.html

Tropical storm Freddy returned to Madagascar in what meteorologists described on Monday as a "rare" loop trajectory, killing four people, including two children as it hit for the second time in as many weeks.

In total at least 11 people have died in Madagascar since Freddy struck the first time in late February.

Another seven were killed in Mozambique, where the tropical storm was also forecast to revisit later this week.

"This 'loop' trajectory is very rare," Rivo Randrianarison, head forecaster at Meteo Madagascar, told AFP.

The last weather system to follow a similar path was recorded in 1998, he said.

... On Monday afternoon Freddy was located about 130 kilometres (80 miles) south-west of the southwestern coastal city of Toliara, with wind gusts of up to 125 kph.

The cyclone was forecast to strengthen as it barrels towards Mozambique.

It was expected to reach the southern African country on Friday.

The storm began to form in the first week of February off northwestern Australia and southern Indonesia.

https://zoom.earth/storms/freddy-2023/

https://www.cyclocane.com/freddy-storm-tracker/

[Jim Hunt]

According to NOAA:

Freddy now holds the world record for “accumulated cyclone energy.”

Animation at the link:

https://twitter.com/NOAASatellites/status/1633149795635441664

[oren]

Wow, quite the resilient storm.

[gerontocrat]

Looks like Freddy might well be heading to the Zambezi Delta, i.e. low altitude instead of mountainous coastal terrain either side, which means slower at losing strength.

From the Zambezi Delta it could head up the narrow Great Rift Valley via the Shire River into Malawi or into the massive Zambezi River Basin.

see terrain map attached, click to enlarge

[Sigmetnow]

Deadly cyclone Freddy has become Earth’s longest-lived tropical storm
The storm has survived for 31 days and rapidly intensified six times
March 7, 2023 at 12:28 p.m. EST

The storm was born in the Indian Ocean on Feb. 6 and has been on a long, winding journey since, walloping both Madagascar and Mozambique and causing at least 21 deaths.

Now, poised to hit Mozambique for a second time, the storm has set a world record for tropical storm longevity, enduring 31 days and counting.

“At this time, it does appear to be a new record holder for ‘longest-lasting’ recorded tropical cyclone … but we are continuing to monitor the situation,” said Randall Cerveny, the World Meteorological Organization’s rapporteur for weather and climate extremes, in a news release.

Over its lifetime, Freddy has tracked more than 5,000 miles since it developed between Western Australia and Indonesia and even attained the strength of a Category 5 hurricane. It’s presently crossing the Mozambique Channel for a third time.

Remarkably, the storm has rapidly intensified six times.

Rapid intensification describes an uptick in winds of 35 mph or greater in 24 hours. Research has shown rapid intensification increasing in frequency in many ocean basins because of rising ocean temperatures linked to human-caused climate change.

Before Freddy, no previous storm in the Southern Hemisphere had rapidly intensified more than three times. In the Northern Hemisphere, it appears that only three storms (Norman ’18, Emily ’05 and John ’94) have undergone four bouts of rapid intensification.

Freddy is continuing to strengthen now, coming off its sixth spate of swift strengthening. Just 24 hours ago, it was a tropical storm with sustained winds of 65 mph. Now it’s the equivalent of a Category 2 hurricane with maximum sustained winds just shy of 100 mph.

Forecasts call for continued strengthening, likely to Category 3 intensity, in the next 72 hours. In Mozambique, preparations are underway for the storm’s return visit after its first landfall there on Feb. 24. Ten people died, 8,000 people were displaced and 28,300 homes were destroyed. Over the past seven days, the storm unloaded up to 20 inches (500 millimeters) of rain on southern portions of the country, according to the WMO.

Freddy will probably be stronger when it hits Mozambique for a second time, though displaced somewhat to the north. …

https://www.washingtonpost.com/weather/2023/03/07/cyclone-freddy-indian-ocean-hurricane/

[gerontocrat]

Image from https://www.metoc.navy.mil/jtwc/jtwc.html

[oren]

This bears repeating in a separate post:
Rapid intensification describes an uptick in winds of 35 mph or greater in 24 hours. Research has shown rapid intensification increasing in frequency in many ocean basins because of rising ocean temperatures linked to human-caused climate change.

[Richard Rathbone]

https://yaleclimateconnections.org/2023/03/record-breaking-cyclone-freddy-approaches-mozambique-again/

Like a bad illness you just can’t clear, Tropical Cyclone Freddy in the South Indian Ocean just keeps coming back. Since getting named Feb. 6 off the northwest coast of Australia, Freddy has been around an astonishing 33 days and is poised to make the third landfall of its lifetime on Saturday, this time in central Mozambique.

But Saturday’s landfall in Mozambique may not be the end of Freddy, either. Projections from a number of models show Freddy reemerging into the Mozambique Channel early next week and re-intensifying over water.

At 12Z Saturday, March 11, Freddy completed an astounding seventh round of rapid intensification, topping out with 110 mph winds just off the coast of Mozambique.

Previous record 4, if it does head back out to sea again after this landfall that could make 8.

So far, Freddy has generated about 80 units of accumulated cyclone energy, or ACE, a measure of cyclone strength over time, according to Dr. Phil Klotzbach of Colorado State. This smashes the previous Southern Hemisphere single-storm record for ACE of 53 formerly held by Cyclone Fantala of 2016. Only 2006’s Hurricane/Typhoon Ioke in the central and western Pacific had a higher lifetime ACE (85.26) than Freddy. The current Joint Typhoon Warning Center forecast predicts Freddy will have about 83 ACE units by Sunday, so if it reemerges over the Mozambique Channel next week, it could eclipse Ioke’s world record for ACE.

[kassy]

Cyclone Freddy: Winds and rain lash Mozambique as storm arrives

Mozambique is being lashed by rain, powerful winds and flooding as Cyclone Freddy makes landfall for the second time in a month.

The southern African nation has received more than a year's worth of rainfall in the past four weeks.

...

https://www.bbc.com/news/world-africa-64928093

[gerontocrat]

Cyclone Freddy
I worked in Rural Development in Malawi for 4 years 40 years ago.By the looks of it not much has changed for most people there in the last 40 years.

Cholera is endemic - seems to stay dormant and then every so often flares up somewhere - usually through contaminated water.



https://www.reuters.com/world/africa/storm-freddy-kills-least-11-malawi-police-2023-03-13/
Storm Freddy kills more than 100 on return to Mozambique, Malawi

BLANTYRE, Malawi/MAPUTO, March 13 (Reuters) - Mozambique and Malawi on Monday were counting the cost of Tropical Storm Freddy, which killed more than 100 people, injured scores and left a trail of destruction as it ripped through southern Africa for the second time in a month over the weekend.

Freddy is one of the strongest storms ever recorded in the southern hemisphere and could be the longest-lasting tropical cyclone, according to the World Meteorological Organization.

It pummelled central Mozambique on Saturday, ripping roofs off buildings and bringing widespread flooding around the port of Quelimane, before moving inland towards Malawi with torrential rains that caused landslides.

The full extent of the damage and loss of life in Mozambique in particular is not yet clear, as the power supply and phone signals were cut off in some parts of the affected area.

The storm has killed 99 people in Malawi, including 85 in the main commercial hub of Blantyre, said the commissioner of the Department of Disaster Management Affairs, Charles Kalemba, at a press briefing.

The central hospital in Blantyre had received at least 60 bodies by early afternoon, Doctors Without Borders (MSF) country director Marion Pechayre told Reuters by telephone, adding that some 200 injured were being treated in the hospital.

The injuries were from falling trees, landslides and flash floods, she said. "A lot of (houses) are mud houses with tin roofs, so the roofs fall on people's heads."

Police spokesperson Peter Kalaya told Reuters that rescue teams had been looking for people in Chilobwe and Ndirande, two of the worst-affected townships in Blantyre, the country's second-largest city, where it was still raining on Monday and many residents were without power.

"Some missing people are feared buried in rubble," Kalaya said.

CRITICAL SITUATION
Malawi's national electricity company EGENCO said that power generation capacity was unstable and that it had experienced total system shutdown twice on Monday. It has shut down all major hydro power stations to protect them from damage, it said.

At least ten people died in Mozambique's Zambezia province, a provincial delegate from the National Institute of Disaster Risk Management, Nelson Ludovico, said on public broadcaster Radio Mozambique, adding that the figures were still provisional.

"The situation is critical in Zambezia province. We can't advance with an accurate picture of the scale of damage because there's no communications with all the regions," Health Minister Armindo Tiago said on public radio.

Guy Taylor, chief of advocacy, communications and partnerships for U.N. children's agency UNICEF in Mozambique, told Reuters from Quelimane that humanitarian agencies there did not have the capacity to deal with a disaster of this size.

"We saw a lot of destroyed buildings and clinics. People's homes had their roofs torn off by the wind. Even before the cyclone hit we saw localised flooding," he said.

The wind had died down on Monday but there was still a lot of flooding that had destroyed crops and created a risk of waterborne diseases, he said.

Mozambique has seen more than a year's worth of rainfall in the past four weeks.

Malawi has been battling the deadliest cholera outbreak in its history, and U.N. agencies have warned the situation could now get worse.

[kassy]

Freddy: The cyclone that lasted more than a month

Malawi, Madagascar and Mozambique are reeling from the effects of Tropical Cyclone Freddy.

More than 400 people have been killed and thousands of homes destroyed.

Freddy has been one of the longest-lived storms ever recorded in the Southern Hemisphere, if not the whole world.

Southern Africa is often battered by cyclones and tropical storms coming in from the Indian Ocean but Freddy was different for several reasons.

How long has Freddy lasted?
Freddy has finally been declared over by the French Meteorological service. The storm was named by the Australian Bureau of Meteorology on 4 February and and finally came to an end on 14 March.

It was strong enough to be officially classified as a tropical system for at least 36 days.

However, we need to wait for confirmation by the World Meteorological Organization before we can say whether it is officially the longest-lasting recorded storm.

What is interesting about Freddy is how far it has travelled. It began its journey off the coast of north-west Australia, crossing the Southern Indian Ocean from east to west, one of only four storms in history to do so.

more:
https://www.bbc.com/news/world-africa-64978492

[Sigmetnow]

NASA’s “TROPICS” satellite constellation will launch next month and reach orbit in time for the North American 2023 hurricane season.  The satellites will monitor the formation and evolution of tropical cyclones, including hurricanes, and will provide rapidly updating observations of storm intensity.

Rocket Lab to Launch NASA's Cyclone-Tracking Satellite Constellation

Rocket Lab USA, Inc., a leading launch and space systems company, today announced it will launch NASA’s TROPICS constellation across two dedicated Electron missions lifting off from Launch Complex 1 in New Zealand next month.

The TROPICS constellation (Time-Resolved Observations of Precipitation Structure and Storm Intensity with a Constellation of Small Sats) will monitor the formation and evolution of tropical cyclones, including hurricanes, and will provide rapidly updating observations of storm intensity. This data will help scientists better understand the processes that effect these high-impact storms, ultimately leading to improved modelling and prediction. The two missions are expected to launch within approximately two weeks of each other in May 2023.  The first launch, named ‘Rocket Like a Hurricane,’ is expected to launch as soon as May 1 NZST (30 April EDT) and the second mission, named ‘Coming to a Storm Near You,’ is expected to follow around May 16 NZST (May 15 EDT).  

The constellation, which is part of NASA’s Earth System Science Pathfinder Program, consists of four CubeSats that require launch to a specific orbit at an altitude of 550 kilometers and inclination of about 30 degrees. All four satellites need to be deployed into their operational orbit within a 60-day period, making Electron the ideal launch vehicle as it enables dedicated launch to unique orbits on highly responsive timelines. The two missions were initially scheduled to lift-off from Launch Complex 2 at the Mid-Atlantic Regional Spaceport within NASA’s Wallops Flight Facility in Virginia but will now take place at Launch Complex 1 in New Zealand to support a Q2 launch window that will see the satellites reach orbit in time for the North American 2023 hurricane season.  …

https://www.asdnews.com/news/aerospace/2023/04/11/rocket-lab-launch-nasas-cyclonetracking-satellite-constellation-new-zealand

Satellite renders and mission patches at Rocket Labs’ thread:
4/10/23 https://twitter.com/rocketlab/status/1645522422194634753

Mission Facts About TROPICS
June 12, 2022
The TROPICS constellation will work in concert to provide microwave observations of storms on Earth, measuring precipitation, temperature, and humidity of a storm as often as every 50 minutes.

Each TROPICS satellite is identical – a 3U CubeSat about the size of a loaf of bread and weighing about 12 lbs.
 
The TROPICS CubeSat payload is a spinning microwave radiometer with highly integrated, compact microwave receiver electronics.
 
TROPICS satellite measures microwave frequencies ranging from about 90 to 205 gigahertz, which can monitor the atmospheric emissions made by water vapor, oxygen, and clouds in the atmosphere. …

https://blogs.nasa.gov/kennedy/2022/06/12/mission-facts-about-tropics/

[gerontocrat]

Tropical Cyclone Ilsa due to hit Western Australia on Thursday with sustained winds of 110 knots, 125 mph 200 kms per hour winds

[gerontocrat]

And Western Australia is duly walloped by Tropical Cyclone Ilsa

[gerontocrat]

Looks like Ilsa missed the centres of population

https://www.theguardian.com/australia-news/2023/apr/14/cyclone-ilsa-moves-inland-with-was-pilbara-warned-to-brace-for-extreme-weather
Cyclone Ilsa moves inland, with WA’s Pilbara warned to brace for extreme weather

On Friday morning Western Australia’s deputy premier, Roger Cook, said while the cyclone largely spared the coastal communities around Port Hedland, it still represented a threat as it moved inland.

As the cyclone crossed over the north-west between Port Hedland and Broome, it was classified as category 5, with winds as fast as 283km/h – the strongest sustained winds that the Bureau of Meteorology has recorded on the mainland.

[gerontocrat]

This science paper suggests coastal hurricanes will become a bigger risk for the US East Coast given continuing AGW. (open access)

https://www.science.org/doi/10.1126/sciadv.adf0259
Increased U.S. coastal hurricane risk under climate change

Abstract
Several pathways for how climate change may influence the U.S. coastal hurricane risk have been proposed, but the physical mechanisms and possible connections between various pathways remain unclear. Here, future projections of hurricane activity (1980–2100), downscaled from multiple climate models using a synthetic hurricane model, show an enhanced hurricane frequency for the Gulf and lower East coast regions.

The increase in coastal hurricane frequency is driven primarily by changes in steering flow, which can be attributed to the development of an upper-level cyclonic circulation over the western Atlantic. The latter is part of the baroclinic stationary Rossby waves forced mainly by increased diabatic heating in the eastern tropical Pacific, a robust signal across the multimodel ensemble. Last, these heating changes also play a key role in decreasing wind shear near the U.S. coast, further aggravating coastal hurricane risk enhanced by the physically connected steering flow changes.

[Sigmetnow]

Mark Sudduth @hurricanetrack
We better hope this El Nino comes on strong because that +AMO look to the Atlantic is legit concerning and very favorable for an active season. Going to be a very interesting 7-8 months ahead!
⬇️ SST anomaly map below
 
< My week in Puerto Rico was very warm & muggy, the usual strong easterlies to cool you off were not there.
Mark Sudduth
And THAT is such a tell-tale sign. The lack of strong easterly flow, part of the -NAO pattern, is helping to warm the Atlantic. Thanks for mentioning this!

< Can you explain what we are looking at? I know El Niño is supposed to suppress activity in the Atlantic, but what does the +AMO do?
Mark Sudduth
Positive AMO is usually associated with more Atlantic TC activity due to warmer than normal SSTs which leads to more favorable conditions at least at or near the surface. Dry air, shear and subsidence can and does limit how favorable conditions get but sometimes things go crazy.

4/26/23, 2:55 PM. https://twitter.com/hurricanetrack/status/1651299085087801382

[be cause]

Myanmar refugees in danger ...


Cyclone Mocha Live: Depression intensifies into storm

Hindustan Times
https://www.hindustantimes.com › india-news › cyclo...
20 minutes ago — Cyclone Mocha live updates: Mocha forming over the Bay of Bengal is likely to intensify into a very severe storm by Friday where wind speeds .

[Sigmetnow]

National Hurricane Center  ‪@NHC_Atlantic‬⁩
NHC has determined that a subtropical storm formed in the Atlantic basin off the northeastern U.S. coast in mid-January 2023, and it will be designated as the first cyclone of the 2023 Atlantic season with ID AL012023.
 
https://www.nhc.noaa.gov/archive/text/PNSNHC/2023/PNSNHC.202305111500.txt
⬇️ Image below from: pic.twitter.com/f047dch647 
  —
As a result, the next cyclone to form in the Atlantic basin this season will be AL022023, and advisories will be issued in AWIPS bin 2. If it begins as a tropical depression, it would be "Tropical Depression Two." If it becomes a tropical storm, it would be named "Arlene."
 
5/11/23, 11:11 AM. https://twitter.com/nhc_atlantic/status/1656678512768749570

[gerontocrat]

Cyclone Mocha in the Bay of Bengal has strengthened. Myanmar & Bangladesh will be hit soon.

JTWC Prognostic Reasoning
WDIO31 PGTW 130900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 01B (MOCHA) WARNING NR
010//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 16.0N 90.0E
   INITIAL INTENSITY: 115 KTS
   GEOGRAPHIC REFERENCE: 392 NM SOUTH-SOUTHWEST OF CHITTAGONG
   MOVEMENT PAST 6 HOURS: NORTHEASTWARD AT 10 KTS
   SIGNIFICANT WAVE HEIGHT: 45 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
THE CORE OF TROPICAL CYCLONE (TC) 01B (MOCHA) HAS QUICKLY
CONSOLIDATED OVER THE PAST SOX HOURS, WITH A WELL DEFINED BUT
CLOUD-FILLED EYE FEATURE EMERGING BY THE 0600Z HOUR. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS VORTICAL HOT TOWERS
(VHTS) DEVELOPING TO THE SOUTHWEST OF THE CENTER, AND QUICKLY
WRAPPING UPSHEAR TO THE NORTH AND NORTHWEST SECTORS, AND SUPPORTING
EMERGENCE OF THE SMALL EYE FEATURE. ANIMATED WATER VAPOR IMAGERY
SUGGESTS THAT THE ATMOSPHERE TO THE NORTH HAS MOISTENED
SIGNIFICANTLY, ELIMINATING A WEDGE OF DRY MID-LEVEL AIR THAT WAS
PREVIOUSLY ENSCONCED TO THE NORTH OF THE CIRCULATION CENTER.
ADDITIONALLY, WATER VAPOR IMAGERY SHOWS STEADY IMPROVEMENT IN THE
POLEWARD OUTFLOW, AND THE SYSTEM IS NOW STARTING TO FEEL THE
EFFECTS OF ENHANCED POLEWARD OUTFLOW INTO THE STRONG JET MAX OVER
SOUTHERN CHINA. THE INITIAL POSITION IS ASSESSED WITH MEDIUM
CONFIDENCE DUE TO THE FACT THAT THE SYSTEM LIES IN THE
HIGH-FORESHORTENING REGION BETWEEN THE GEOSTATIONARY SATELLITES,
AND THERE HAS BEEN NO RECENT MICROWAVE IMAGERY TO RESOLVE THE
POSITION AMBIGUITY. THE SYSTEM HAS ALSO BEEN EXHIBITING A LARGE
WOBBLE IN THE MOTION VECTOR, WHICH HAS COMPLICATED THE POSITIONING.
THE INITIAL INTENSITY IS ASSESSED WITH HIGH CONFIDENCE BASED ON A
BLEND OF AGENCY CURRENT INTENSITY ESTIMATES SUPPORTED BY THE
SATCON, ADT AND OPEN-AIIR OF 113 KNOTS. THE SYSTEM HAS PICKED UP
SPEED NOW THAT IT HAS ROUNDED THE RIDGE AXIS, MOVING OFF THE
NORTHEAST AT AROUND 10 KNOTS. CONDITIONS ARE FAVORABLE FOR FURTHER
INTENSIFICATION, WITH LOW (5-10 KTS) VERTICAL WIND SHEAR (VWS),
WARM (31-32C) SSTS AND STRONG POLEWARD OUTFLOW.

INITIAL WIND RADII BASIS: SCATTEROMETER DATA

CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) CENTERED OVER THE NORTHERN PHILIPPINES.

AGENCY DVORAK AND AUTOMATED FIXES:
   PGTW: T6.0 - 115 KTS
   KNES: T6.0 - 115 KTS
   DEMS: T5.5 - 102 KTS
   CIMSS SATCON: 113 KTS AT 130405Z
   CIMSS ADT: 107 KTS AT 130630Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 5-10 KTS
   SST: 31-32 CELSIUS
   OUTFLOW: STRONG POLEWARD

ANALYSIS CONFIDENCE:
   INITIAL POSITION: MEDIUM
   INITIAL INTENSITY: HIGH
   INITIAL WIND RADII: HIGH

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TC 01B WILL CONTINUE TO ACCELERATE ON A STEADY
NORTHEASTWARD COURSE THROUGH THE FORECAST PERIOD, ALONG THE
NORTHWEST PERIPHERY OF THE DEEP STR TO THE EAST. LANDFALL IS
EXPECTED AT OR NEAR TAU 24 IN THE VICINITY OF SITTWE, MYANMAR. DUE
TO THE IMPROVING ENVIRONMENTAL CONDITIONS, INCLUDING DECREASING
VWS, IMPROVING POLEWARD OUTFLOW AND MOISTENING OF THE ATMOSPHERE IN
THE DOWN-TRACK DIRECTION, ADDITIONAL NEAR-TERM INTENSIFICATION IS
LIKELY. IF THE NASCENT EYE FEATURE CAN CONTINUE TO CLEAR-OUT, IT IS
POSSIBLE THE SYSTEM COULD REACH 130 KNOTS WITHIN THE NEXT 6-12
HOURS. HOWEVER, BY TAU 12 CONDITIONS BECOME SLIGHTLY LESS
FAVORABLE, WITH INCREASED SHEAR BEING THE PRIMARY FACTOR IN THE
ANTICIPATED WEAKENING TREND. THE SYSTEM IS EXPECTED TO WEAKEN
SLIGHTLY, TO 115 KNOTS, JUST PRIOR TO LANDFALL. IMMEDIATELY AFTER
LANDFALL, THE SYSTEM WILL RAPIDLY WEAKEN AS IT IS TORN APART BY
HIGH SHEAR AND TERRAIN INTERACTION, FULLY DISSIPATING BY TAU 48
OVER FAR NORTHERN MYANMAR.

MODEL DISCUSSION: DETERMINISTIC AND ENSEMBLE TRACK GUIDANCE IS IN
TIGHT AGREEMENT ON THE NORTHEASTWARD TRACK, WITH JUST 55 NM OF
SPREAD AT LANDFALL, LENDING HIGH CONFIDENCE TO THE JTWC FORECAST
TRACK. INTENSITY GUIDANCE IS ALSO IN VERY TIGHT AGREEMENT, HOWEVER
THE JTWC FORECAST DEVIATES FROM THE GUIDANCE THROUGH TAU 12. ALL
MEMBERS OF THE INTENSITY CONSENSUS AGREE THAT THE SYSTEM WILL NOT
INTENSIFY FURTHER AND BEGIN TO WEAKEN THE SYSTEM FROM TAU 00, WITH
THE CONSENSUS MEAN INTENSITY AT LANDFALL OF 100 KNOTS. BASED ON
CURRENT INTENSITY TRENDS AND ENVIRONMENTAL ANALYSIS, THE JTWC
FORECAST DEVIATES FROM THE GUIDANCE, TAKING THE SYSTEM TO 125 KNOTS
WITH A POSSIBILITY OF A SLIGHTLY HIGHER PEAK, FOLLOWED BY WEAKENING
THROUGH LANDFALL. THE LANDFALL INTENSITY IS APPROXIMATELY 15 KNOTS
HIGHER THAN THE GUIDANCE WOULD SUGGEST. AFTER LANDFALL THE OFFICIAL
FORECAST REJOINS THE CONSENSUS. BASED ON THE DEVIATION FROM THE
GUIDANCE PACKAGE, CONFIDENCE IN THE JTWC FORECAST INTENSITY IS
MEDIUM.

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: HIGH
   INTENSITY 0 - 72 HR: MEDIUM//
NNNN

[gerontocrat]

JTWC now says Cyclone Mocha will landfall at 115 knots
Those refugee camps on the coast haven't got a chance to avoid disaster - just look at the image below.

https://www.theguardian.com/world/2023/may/13/cyclone-mocha-threatens-worlds-largest-refugee-camp-on-myanmar-bangladesh-border
Cyclone Mocha threatens world’s largest refugee camp on Myanmar-Bangladesh border

Predicted to make landfall on Sunday, preparations are under way for a partial evacuation of the camp in Cox’s Bazaar

Tropical cyclone Mocha intensified to become “very dangerous”, the World Meteorological Organisation has said, warning of violent winds, floods and possible landslides in Bangladesh which could hit the world’s biggest refugee camp in Cox’s bazar.

Cyclone Mocha is predicted to make landfall on Sunday near the Bangladesh-Myanmar border, according to India’s meteorological office, packing winds of up to 175km/h (108mph).

The office predicted a storm surge of between two and two-and-a-half metres (six to eight feet) for the low-lying coastal region, which on the Bangladeshi side is home to sprawling camps hosting hundreds of thousands of Rohingya refugees. Most of them fled there after a military-led crackdown in Myanmar in 2017.

UN refugee agency spokesperson Olga Sarrado said preparations were under way for a partial evacuation of the camp, if needed. The agency was also preparing tens of thousands of hot meals and jerrycans, she said.

The World Health Organisation said it was pre-positioning 33 mobile medical teams and 40 ambulances as well as emergency surgery and cholera kits for the camp.

In Myanmar, the WHO was pre-positioning 500,000 water purification tablets among other supplies which amount to the entire monsoon season stocks.

[gerontocrat]

Mocha approaches landfall with 135knot sustained winds but will reduce slightly in shallow coastal waters ideal for maximising storm surge.

[gerontocrat]

Super Typhoon Mawar to hit the US Territory of Guam in a few hours packing 140knot sustained winds.

FORECAST DISCUSSION: STY MAWAR IS EXPECTED TO REMAIN AT OR NEAR
SUPER TYPHOON INTENSITY FOR THE DURATION OF THE FORECAST PERIOD.
THE PRIMARY INHIBITOR TO ADDITIONAL INTENSIFICATION REMAINS THE
IMPACT OF INNER-CORE DYNAMICS, INCLUDING THE POSSIBILITY OF EYEWALL
REPLACEMENT CYCLES. THE CURRENT FORECAST CALLS FOR MARGINAL
INTENSIFICATION TO 140 KNOTS OVER THE NEXT 12 HOURS BASED ON HIGHLY
FAVORABLE ENVIRONMENTAL CONDITIONS. AS PREVIOUSLY ANTICIPATED, THE
SYSTEM IS TURNING TOWARD A WEST-NORTHWESTWARD TRACK FOLLOWING THE
FLOW ASSOCIATED WITH A BUILDING SUBTROPICAL RIDGE TO THE NORTH. THE
PROJECTED TRACK WILL CARRY STY MAWAR OVER THE ISLAND OF GUAM WITHIN
12 TO 18 HOURS, ALMOST CERTAINLY INCLUDING PASSAGE OF THE INNER
EYEWALL. STY 02W WILL CONTINUE TO FOLLOW SOLIDLY ENTRENCHED FLOW
ASSOCIATED WITH THE STR THROUGHOUT THE FORECAST PERIOD REMAINDER OF
THE FORECAST PERIOD, APPROACHING THE RIDGE AXIS AROUND TAU 120.

MODEL DISCUSSION: NUMERICAL MODEL TRACK FORECAST GUIDANCE IS IN
VERY GOOD AGREEMENT THROUGH THE ENTIRETY OF THE FORECAST PERIOD,
WITH NO NOTEWORTHY OUTLIERS, AND THE CURRENT FORECAST IS PLACED
WITH HIGH CONFIDENCE NEAR THE MULTI-MODEL CONSENSUS. AVAILABLE
INTENSITY FORECAST GUIDANCE INDICATES LITTLE OR NO ADDITIONAL
NEAR-TERM INTENSIFICATION. THROUGHOUT THE REMAINDER OF THE
FORECAST, ALL AVAILABLE SOLUTIONS LIE IN THE STRONG TYPHOON TO
SUPER TYPHOON RANGE. GIVEN THE ONGOING POTENTIAL FOR INNER-CORE
STRUCTURAL CHANGES AND SOME SPREAD IN MODEL FORECAST GUIDANCE,
CONFIDENCE IN INTENSITY FORECAST IS MEDIUM.



https://www.stripes.com/theaters/asia_pacific/2023-05-23/guam-typhoon-mawar-evacuations-10207523.html
Guam warns of ‘direct hit,’ orders evacuations as Mawar reaches super typhoon status

The governor of Guam ordered residents in low-lying areas to evacuate Tuesday as Super Typhoon Mawar barreled toward the island.

Islanders were advised by emergency authorities to seek immediate shelter, with damages expected overnight Tuesday and peak typhoon winds expected Wednesday.

“Super Typhoon Mawar is expected to make a direct hit or very near passage for Guam,” the island’s Joint Information Center said in a 6:30 p.m. bulletin. “There is a potential of a catastrophic and devastating event for Guam. Typhoon force winds are expected Wednesday morning, with peak conditions around midday.”

Gov. Lou Leon Guerrero and Joint Region Marianas, the military installation management command on Guam, set Condition of Readiness 1 around 2:30 p.m. Tuesday.

“Current forecasts are not favorable to our island — which we have been carefully tracking and preparing for,” Leon Guerrero told residents in a video message.

The storm is predicted to pass almost directly over the capital, Hagatna, and Naval Base Guam, 15 miles southwest of Andersen Air Force Base, between 2 p.m. and 4 p.m. Wednesday.

“This is a very serious situation with steadily deteriorating conditions,” the bulletin said.

Mawar was upgraded to a super typhoon around 5 p.m. Tuesday, May 23, 2023.
Mawar was upgraded to a super typhoon around 5 p.m. Tuesday, May 23, 2023. (Joint Typhoon Warning Center)

Mawar was upgraded to a super typhoon around 5 p.m. Tuesday with sustained winds of 155 mph and 195 mph gusts, according to the Joint Typhoon Warning System. The island is braced for 161 mph sustained winds with 196 mph gusts early Wednesday morning.

Leon Guerrero ordered anyone in “low-lying, flood-prone and coast areas” to evacuate and mobilized the Guam National Guard to assist with the efforts. She urged people to stay calm, remain informed and act immediately.


“My greatest concern and worry is your safety,” she said in the video posted on her office’s YouTube channel. “We must act now to ensure the protection of our people and your safety.”

The naval base, Andersen and the Marine Corps’ Camp Blaz urged U.S. service members to seek shelter throughout the day on Tuesday.

Navy ships were sent away from the island as a standard precautionary measure, according to naval base spokeswoman Valerie Maigue, who said the installation has been preparing for Mawar for several days.

“We’ve been tracking this storm since late last week, and we’ve notified our families well in advance,” she told Stars and Stripes by phone Tuesday.

The base notified service members Tuesday afternoon that anyone affected by the evacuation order could contact the command duty officer for shelter and temporary housing by calling (671) 488-7147.

“Personnel who intend to evacuate to [Naval Base Guam] temporary housing or any other private residence, should contact their immediate supervisor or their respective Command Duty Officers to provide their whereabouts and contact information,” states a post on the base’s official Facebook page.

All aircraft at Andersen have either departed or are sheltered in hangars, base spokeswoman Capt. Katie Mueller told Stars and Stripes by text message Tuesday evening. The base advised everyone to follow the governor’s order and remain indoors.

Mawar could potentially be the strongest storm to lash Guam since Super Typhoon Pongsona passed the island in December 2002 with gusts of 173 mph.

A Category 5 storm brings “catastrophic damage” and may collapse walls and roofs, cause long-lasting power outages and render much of the affected area uninhabitable for weeks or months, according to the National Oceanic and Atmospheric Administration.

[vox_mundi]

Atlantic Hurricane Season Forecast to Have at Least 12 Named Storms
https://www.noaa.gov/news-release/2023-atlantic-hurricane-season-outlook

NOAA forecasters with the Climate Prediction Center, a division of the National Weather Service, predict near-normal hurricane activity in the Atlantic this year. NOAA’s outlook for the 2023 Atlantic hurricane season, which goes from June 1 to November 30, predicts a 40% chance of a near-normal season, a 30% chance of an above-normal season and a 30% chance of a below-normal season.

NOAA is forecasting a range of 12 to 17 total named storms (winds of 39 mph or higher). Of those, 5 to 9 could become hurricanes (winds of 74 mph or higher), including 1 to 4 major hurricanes (category 3, 4 or 5; with winds of 111 mph or higher). NOAA has a 70% confidence in these ranges

El Nino’s potential influence on storm development could be offset by favorable conditions local to the tropical Atlantic Basin. Those conditions include the potential for an above-normal west African monsoon, which produces African easterly waves and seeds some of the stronger and longer-lived Atlantic storms, and warmer-than-normal sea surface temperatures in the tropical Atlantic Ocean and Caribbean Sea which creates more energy to fuel storm development. These factors are part of the longer term variability in Atlantic atmospheric and oceanic conditions that are conducive to hurricane development — known as the high-activity era for Atlantic hurricanes — which have been producing more active Atlantic hurricane seasons since 1995. .

NOAA officials said Thursday that the effects of climate change could mean that storms yield more precipitation and slightly stronger winds than ever before, citing Hurricane Harvey, which dropped a record 5 feet of water on Texas in 2017.

... NOAA also issues seasonal hurricane outlooks for the eastern Pacific and central Pacific hurricane basins.

https://www.cpc.ncep.noaa.gov/products/Epac_hurr/index.shtml

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... for 26°C IsoTherm ...

Ocean Heat Content Products Images
https://www.ospo.noaa.gov/data/ocean/ohc/

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[Sigmetnow]

Some stats on Super Typhoon Mawar from May 25:
 

Matthew Cuyugan ⁦‪@MatthewCuyugan‬⁩
 
Super Typhoon #Mawar continues to become a very powerful storm, now having 1-min sustained winds of 155 kts (~285 km/h) in the US scale – as a Category 5 storm.

In terms of one-minute sustained winds, it becomes the strongest tropical cyclone for the month of May in the Western Pacific basin since the beginning of the satellite era – ties with STY Damrey (2000).

Meanwhile, the RSMC Tokyo has maintained its 10-min sustained winds of 110 kts (205 km/h) and a central pressure of 910 hPa. …

5/25/23, 3:35 PM. https://twitter.com/matthewcuyugan/status/1661818241621331969

Andrew Freedman ⁦‪@afreedma‬⁩
 
Super Typhoon Mawar is now up to SUSTAINED winds of 180 mph, testing the upper limits of its theoretical potential intensity (how strong it could get given ocean temperatures, atmospheric conditions, etc.). A rare beast.

5/25/23, 5:25 PM. https://twitter.com/afreedma/status/1661845867052126208

[vox_mundi]

Tropical Wave Invest 91-L Forms in Gulf, Expected to Bring Florida Rain
https://www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=7

The National Hurricane Center says an area of low pressure in the Gulf of Mexico has become tropical wave Invest 91-L.



Environmental conditions appear marginally favorable for additional development over the next day or so, and a short-lived tropical depression or storm could form over that time span as the system meanders over the northeastern Gulf of Mexico. However, by this weekend environmental conditions are forecast to become unfavorable for additional development as the system drifts southward, likely remaining offshore over the Gulf of Mexico.

Today marks the first day of the Atlantic hurricane season, which will run until November 30. The long-term averages for the number of named storms, hurricanes, and major hurricanes are 14, 7, and 3, respectively.

[prokaryotes]

Some stats on Super Typhoon Mawar from May 25..

From May 30

Super Typhoon Mawar is among the top ten most powerful on record globally.
Main near-term #globalwarming hazards according to the latest #IPCC report include "increased proportion of and peak wind speeds of intense tropical cyclones (high confidence)".

https://twitter.com/rahmstorf/status/1663478115761307649

[Sigmetnow]

2023 Atlantic Hurricane Season Names

* Names replaced from 2017: Harvey, Irma, Maria and Nate

Facts About Each 2023 Name
https://weather.com/storms/hurricane/news/2023-05-04-2023-atlantic-hurricane-season-name-list

[John_the_Younger]

I was looking for information about the Atlantic Ocean basin's Tropical Depression One (in January 2023) and found this chart of forecasts for this year.

From KPRC TV:

The University of Barcelona collects all the hurricane forecasts from universities, private industries, and government agencies and puts them on a very cool, interactive page for everyone to view. Here’s what it looks like:

 And just for the record Tropical Storm Arlene formed in the Gulf of Mexico, moved southwards then dissipated near Cuba. (Let's hear it for "fish" storms!)

Date          Time                 Lat   Long         Speed        Pressure   Storm Type
Jun 1   21:00 GMT   28   -86.6   35 mph   1,007 mb   Tropical Depression
...
Jun 2   18:00 GMT   26.7   -86.2   40 mph   1,002 mb   Tropical Storm
...
Jun 3   15:00 GMT   24.2   -85.1   35 mph   1,000 mb   Tropical Depression
Jun 3   21:00 GMT   23.7   -84.7   30 mph   1,001 mb   Post-Tropical Cyclone

[Richard Rathbone]

Levi's first video of the season is up at https://www.tropicaltidbits.com/ with a discussion on the tropical waves coming off Africa. Mostly on 92L very likely to form a storm in the next couple of days, now 90% in NHC forecast.

https://www.nhc.noaa.gov/cyclones/

[vox_mundi]

Cyclone Leaves 13 Dead In Brazil
https://phys.org/news/2023-06-cyclone-dead-brazil.html
https://watchers.news/2023/06/19/extreme-rainfall-hits-southern-brazil-leaving-at-least-11-people-dead-and-20-missing/

An intense extratropical cyclone which tore through southern Brazil has killed at least 13 people and forced thousands from their homes, authorities said Sunday.

Torrential rain and strong winds on Thursday and Friday caused damage in dozens of towns in the state of Rio Grande do Sul, including its capital Porto Alegre—the latest in a string of weather-related disasters to hit South America's biggest country.

Reports from mayors of the affected cities highlight the severity of the storm, with twice the amount of rain falling in 24 hours than typically expected for the entire month of June. The Mayor of Maquine noted on social media that rainfall in his city surpassed 294 mm (11.6 inches) in a single day.

The storm has brought record rainfall of 300 mm to 400 mm (11.8 inches to 15.7 inches) causing flooding in municipalities of Greater Porto Alegre. This has led to the largest flood in Vale dos Sinos in a decade, with the Sinos River reaching a peak level of 7.60 m (24.9 feet), the highest since August 2013 when it reached 7.86 m (25.8 feet), Met Sul reported.

In Sao Leopoldo, about half-an-hour drive from Porto Alegre, 246mm (9.7 inches) of rain fell in 18 hours, “a level never seen before in the history” of the city of 240,000 inhabitants, stressed Porto Alegre Mayor Ary Jose Vanazzi.

Further rainfall and cold temperatures are expected in the middle of next week, however, potentially further exacerbating the situation for those already impacted.Brazil has been hit by a series of deadly weather disasters in recent years, which experts say are being made worse by climate change.

[vox_mundi]

Tropical Storm Bret Is Forecast to Become a Hurricane by Wednesday
https://amp.cnn.com/cnn/2023/06/19/weather/tropical-storm-bret-windward-islands/index.html

A tropical storm named Bret has formed over the central Atlantic Ocean and will likely become a hurricane on Wednesday, the National Hurricane Center said Monday afternoon.

The storm now has winds of 40 mph and continues to move quickly to the west, according to the center.

https://www.nhc.noaa.gov/#Three

“Environmental conditions appear conducive for strengthening over the next few days, with a much warmer than normal ocean in the depression’s path, along with plentiful mid-level moisture and light shear,” the center said.

The storm is forecast to become a hurricane on Wednesday. It is still too early to tell what impacts, if any, it will have on the US mainland.

The storm could impact the Leeward or Windward islands later this week. The Leeward Islands, located where the northeastern Caribbean Sea meets the western Atlantic, include the Virgin Islands, Saint Martin, and Antigua and Barbuda. To the south are the Windward Islands: Dominica, Grenada, Martinique and others.

[Paddy]

Hot water is, unsurprisingly, key to this year’s early start to the hurricane season:
https://www.nbcmiami.com/weather/hurricane-season/the-2023-hurricane-season-is-off-to-a-sizzling-start-hot-water-is-to-blame-john-morales/3056423/?amp=1

The 2023 hurricane season is off to a sizzling start. Hot water is to blame: John Morales

2023’s Bret is only the fourth June system to form in the deep tropics of the North Atlantic since 1851.
By John Morales • Published June 19, 2023 • Updated on June 19, 2023 at 8:41 pm
 


NBC Universal, Inc.
Bret is only the fourth named tropical system to form in the deep tropics of the North Atlantic since 1851. NBC6’s Hurricane Specialist John Morales has more

Tropical Storm Bret formed on Monday afternoon midway between Africa and the Antilles. The storm is moving quickly towards the west at 21 miles per hour.

2023’s Bret is only the fourth June system to form in the deep tropics of the North Atlantic since 1851. I’m referring to the area between the Cabo Verde Islands and the Lesser Antilles known as the Main Development Region (MDR) of the Atlantic, where storms normally wait until August and September to develop.

Despite this region of the world being located in tropical latitudes, water temperatures there are normally kept cooler longer into the summer thanks to the cold Canary Current which travels down from a region south of Iceland and Greenland. Plus, colder water usually rises from the deeper ocean near the African coast thanks to the typical trade winds that blow warmer surface waters from east to west and away from the Mother Continent, leading to a process known as upwelling.

This year, however, those trade winds have been very weak. Not only do weaker trade winds result in warmer sea surface temperatures in the MDR, but they also blow less sand and dust into the Atlantic off of the Saharan and Sahel regions of Africa. Less Saharan dust means fewer particles floating around that can block out and scatter sunlight. Therefore, the sun heats the ocean faster.

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A Saharan Air Layer — our pal SAL — is also typically accompanied by a stable slice in the atmosphere which tends to place a lid on the vertical growth of tropical thunderstorms. The resulting dry air often mixes in with fledgling tropical systems and weakens them.

Given the combination of factors that I just described, perhaps tropical development was to be expected in that part of the Atlantic. But it’s still a very rare event, as only about 1% of all named systems have formed in the MDR during June going back 173 years.

If you were to remember just one of the elements that led to this June surprise, the water temperature is the one to blame. The water in the MDR is averaging 81.5 degrees right now, and tropical systems need sea surface temperature readings above 80 °F to form.

Hurricane Season
The NBC 6 First Alert Weather team guides you through hurricane season



21 HOURS AGO
Tropical storm warnings posted for more islands as Caribbean awaits Bret


JUN 20
Tropical Storm Bret strengthens as TS watch issued for several islands: NHC
What happens next?

For now, the system will likely strengthen quickly as the work week progresses. By this weekend, the National Hurricane Center is forecasting a Hurricane Bret tangling with the Lesser Antilles and possibly the Virgin Islands, Puerto Rico and/or Hispaniola. But upper level wind shear could start to counteract the effects of the hot ocean by the weekend too, potentially weakening the system.

John Morales is NBC6's Hurricane Specialist.

[Richard Rathbone]

Not just one in June

https://yaleclimateconnections.org/2023/06/tropical-storm-bret-nears-the-lesser-antilles-as-a-new-system-gains-strength/

On Thursday, June 22, Tropical Storm Bret was approaching the central islands of the Lesser Antilles. Meanwhile, newborn Tropical Depression Four – predicted to become Tropical Storm Cindy – was gathering strength in the central tropical Atlantic.

There’s a solid consensus among forecast models that TD 4 will strengthen into Tropical Storm Cindy, as predicted by NHC to happen as soon as Thursday night. If so, it’ll be history in the making. Across NOAA hurricane records that go back to 1851, only a handful of tropical cyclones have formed in the Main Development Region during June, and no June has spawned two tropical cyclones there. Sea surface temperatures over the region are typically too cool to support tropical development until later in the summer, and it’s usually too early for the sequence of easterly waves streaming from Africa into the region to get rolling. But the surface waters have been record-warm this year, and a robust wave train has set up well ahead of schedule.

One might be accounted a misfortune, but two looks like carelessness with CO2.