WEATHERAmerica Newsletter; Monday, May 25, 2026; EXTENDED PERIOD FORECAST

[Larry Cosgrove]

EXTENDED PERIOD FORECAST

(Between Day 11 And Day 15)

 

What Exactly Is Ailing The Numerical Models? Will June Be Cool Or Warm?

CIMSS (2)

TropicalTidbits.Com (Dr. Levi Cowan) (3)

NOAA/PMEL

NOAA/CPC

HPRCC/University Of Nebraska (2)

Environment Canada

WeatherBELL (9)

I admit that with all of the talk of "Super El Nino", crazed numerical model forecasts and impending changes in the NOAA data output process, it is enough to make many dizzy and unable to get a fair assessment of how the actual weather will turn out. But step away from the hype and the bureaucracy, and some aspects of the Summer 2026 prediction will become clear. First, we should take a look at temperature and precipitation patterns. Then how the tropical cyclone potential may unfold.

Recent output of the longer term models has fluctuated wildly between widespread heat across the continent and the outlining of a bizarre southern and eastern USA cold wave that looks like something out of early March rather than the start of meteorological summer. The upper air forecasts coincident with this supposed polar regime are not supportive of major cPk advection. Of course, the early AM outlines on Memorial Day more or less threw the cold scenario in the proverbial trash can. All of the series, especially the model weeklies, had a much warmer perspective. There may be cooling in Texas and the Gulf Coast in the 6-10 and 11-15 day ranges due to cloudiness and precipitation, but realistically much of the nation to the right of the Continental Divide is likely to be hot and dry. Incidentally, seeing how arid and heated the western third of the lower 48 states has been, I have my doubts about the 500MB low and cold pool across the Pacific shoreline and Intermountain Region in the longer term. That part of the country has been almost continuously dried and heated this Spring, with fires already occurring in California tree stands.

There are two forms of model guidance showing a tropical cyclone threat in either the Caribbean or Sargasso Seas in the 11-15 day range. The warmth of the water helps the idea, while shearing southern branch wind profiles push back on the possibility. If anything in the way of a disturbance does form, the track predictions are into either the open Atlantic Ocean or into Belize or the Yucatan Peninsula. Late Spring warm-core developments are almost always troublesome for excessive rain production, but take a back seat to the possibility of a long-lived heat wave. Which is what the American longer-term outlines are showing.

Prepared by Meteorologist LARRY COSGROVE on 
Monday, May 25, 2026 at 2:15 P.M. CT

Disclaimer: 
The previous statements are my opinions only, and should not be construed as definitive fact. Links provided on this newsletter are not affiliated with WEATHERAmerica and the publisher is not responsible for content posted or associated with those sites.

Copyright 2026 by Larry Cosgrove

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