WEATHERAmerica Newsletter, Saturday, March 7, 2026; SHORT And MEDIUM RANGE OUTLOOKS

[Larry Cosgrove]

SHORT RANGE OUTLOOK

(Through The Next 72 Hours)

 

Cold Canada, Warm USA Scenario Has Inklings Of What May Happen This Summer

METEOBLUE

TrueWx.Com (3)

ECMWF

College Of DuPage Weather Laboratory (3)

When I review options for the coming JJAS/summer months (which I am starting to do with a projected outlook post on April 23), I look for a transition in ENSO, similarities to Spring upper air 500MB height and sea surface temperatures. We should be leaving La Nina behind momentarily, reaching neutral readings in the equatorial Pacific Ocean on or just after April 1, and seeing entry to El Nino in the first week of June.Note the consolidation of the massive cAk gyre over Hudson Bay, with a mostly warm U.S. vs. a still cold, with ice and snow potential fairly high in Canada.

There will be some erosion of the warm weather over the Pacific Northwest into Montana and the Dakotas. The Mexican heat ridge has a weakness to its right, with a weak frontal structure and very unstable air. At some point a storm organizing off of Baja California will travel east-northeast, using the discontinuity as a sort of railroad track in the period March 10 - 14. This is why a severe weather threat will likely appear from the south central states into the Ohio and Tennessee Valleys during the new week. Most of the Desert and Intermountain Regions are likely to be very warm and dry as the ridge complex in Mexico is forecast by most guidance to amplify.

Watch that subtropical high coming into the Southwest; it could play a very important part in your summer plans!

 

MEDIUM RANGE OUTLOOK

(Four To Ten Days From Now)

 

(Very) Warm West Vs. (Getting) Colder East Alignment; Rude Surprise On St. Patrick's Day?

METEOBLUE

PivotalWeather.Com (4)

ECMWF (4)

College Of DuPage Weather Laboratory (3)

We start off with the obvious, that Spring has gotten off to an early start in much of the lower 48 states. Somewhat like 1980, 1986, and 2023, with rough and tumble thunderstorm events followed by a warmer turn in the Southwest and south central states. But like those years, there were cold surprises. This March most likely will see a colder turn over the eastern half of the nation. And perhaps something else in the Midwest, Great Lakes, and the Northeast.

All of that snow and cold over Canada could get tapped as a cAk intrusion by next weekend. So while the balmy start to the season in some places may get superseded by a cold shot, there will also be the potential for a substantial winter storm. The idea is that the heat ridge in Mexico amplifies sharply into a +PNA signature with an axis running from British Columbia to the Sonoran Desert.With a classic, and rather large, Hudson Bay vortex, drainage will likely get going from the Prairie Provinces and Ontario to points south and east. It may take a while for the chill to reach Texas and the Deep South, but confidence is high that those locations will get a meaningful rise in heating demand on and after St. Patrick's Day. If a digging shortwave from Saskatchewan keeps its integrity and reaches the Carolinas on March 17, we could see explosive redevelopment in a classic "MIller B" cyclogenesis that just might deliver a smack to the Mid-Atlantic and New England states, then the Maritime Provinces and Atlantic Canada. I rate the risk of a snow event in those regions around 2 in 5 as we start the longer term.