the entire CONUS has been text book El Nino more often than not this winter.
Not the case. For starters, the Southwest is a quarter of the continental US. We have not had a single day of 'El Nino weather' since October unless you count the wildly misattributed mid-January event.
US weather largely comes off the jet stream and Pacific Ocean, not Canada per se. If the storms have indeed been deflected farther north this year, it follows the weather in the Northwest is also highly abnormal (not El Nino pattern). So just for starters everything west of Denver is abnormal.
In my view, no such thing as a distinctive El Nino weather pattern exists, meaning loosely if you saw exactly the same pattern during La Nina or La Nada you would not say 'hey what is going on, this is an El Nino weather pattern'.
A distinctive El Nino weather pattern in the NH would imply someone could demonstrate the ability invert the weather. That is,
I give you double-blinded northern hemisphere weather data from 1980-2015,
you get back to me with the status of the equatorial South Pacific for each of those masked years. If not, there's no such thing as an objective distinctive El Nino weather pattern.
In my view, only textbook applicable here is from Psychology 101, the chapter entitled 'The Power of Suggestion'. When people are told every day for months on end on weather tv that equatorial south pacific is in a gonzo El Nino condition, anything and everything that later happens in the US will be attributed to El Nino.
If it had instead been reported that 2015/16 was a gonzo La Nina/Nada year and to expect a horrific continuation of the drought (which is what is happening but for other reasons), the identical anything and everything in the US would now be attributed to the ongoing gonzo La Nina/Nada. (I am making this prediction at the 99.9% confidence level.)
These rain statistics, if you care to call just two years 'statistics' ie 1982/83 and 1997/98, assume a flat climatology (have no adjustment to the rapid change in surface temperature and water vapor content). Historic weather statistics are very rapidly losing their value under climate change. We couldn't predict diddley before and now it's even harder.
El Nino reminds me of a roulette wheel. The croupier said 'les jeux sont faits' back in mid-December, so NOAA bet on the black (more rain than average, happens half the time). Something was really off with the weather, so I bet on the red back on a Dec 10th post. As did the Old Farmers Almanac back in mid-Oct.
NCAR's Trenberth had the sense to
wait until the wheel stopped spinning on 01 Mar 2016 when, ignoring repeated cries of 'rien ne va plus' from the croupier, he changed his bet from black to red!!!
If you recall the investigation of the Challenger disaster (the closest thing to this year's El Nino predictions), nothing would have come of it had not NASA appointed a reputable physicist (Richard Feynman) to the committee, thinking 'what does a quantum field theorist guy know about gaskets'.
That's what I am calling for here with El Nino 2015/16: an independent investigating committee of real physicists who come in knowing absolutely nothing about climatology/meteorology. These folks are quick studies; we'd soon get a good idea on what went wrong, why it went wrong, and whether we can fix it.
I tend to think not. The ocean warming, yes; the tropical breezes, never; tele atmospheric physics, progress is possible; other competing effects that trump El Nino, too soon to say; moving beyond wait-and-see, not likely.
I do think this year presents a great opportunity to focus on the dominant processes affecting Pacific storm tracks but that is getting lost defending Received Wisdom around El Nino. The aforementioned psychology textbook has a good chapter called 'Responses to Cognative Dissonance' but it is very seldom read.