WEATHERAmerica Newsletter; Saturday, June 6, 2026; EXTENDED PERIOD FORECAST

[Larry Cosgrove]

EXTENDED PERIOD FORECAST

(Between Day 11 And Day 15)

 

A Cool Canada Vs. (Mostly) Hot USA Pattern?

WMO/Beijing

CIMSS (3)

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

NOAA/PMEL

NOAA/CPC

ECMWF

HPRCC/University Of Nebraska (2)

Environment Canada

WeatherBELL (9)

There is talk about a cold frontal passage through the Midwest, Great Lakes, and the Eastern Seaboard in the longer term. For the most part I think that is correct, but I urge caution to take a look at resumption of strong heat ridging first. The CMA/GFS model initiation at 0z shows the dominance of the broad subtropical high across the Northern Hemisphere;  weakness over Mexico into the western states is being joined by a stronger trough in the Pacific Northwest, which should move through the center and eastern portion of the continent between June 14 - 18. This being peak sunshine period means that you will have to account for moderation of the cold pool, which implies the heat ridge indentation will not be pronounced,  and likely to rebound. This should be a case where Canada gets the greater amount of rain and thunderstorms, and stays normal to cool (much like the NAEFS ensemble members are suggesting). The northern tier of the USA may see some intense convection, with potential for the Great Lakes and Midwest to turn substantially cooler. But I favor the slower changes shown by the operational ECMWF panels, which bring the IcP air mass into the eastern states somewhat briefly in the 11-15 day range.

I also suspect that the ridge returns to its natural hot/dry realm for the West/California for most of June. The model guidance has been so wrong about the western states this spring and summer (overdoing rain and cooler air), and now the 16-20 and 21-25 day range depictions are going full-tilt back into a heatwave that should extend into Texas and the Great Plains. The monthly forecasts for July will, eventually, turn into a hot West/Central vs. mild East alignment. El Nino climatology strongly favors a +PNA shift in the second half of summer. Cold fronts will start to have a larger impact on weather to the right of the Mississippi River once we get past the July 4th holiday weekend. If somehow a tropical cyclone were to organize in the Caribbean Sea, Gulf of Mexico, or Sargasso Sea and move along or just to the right of the East Coast, then the cooler turn will happen sooner. But as of now, it is a Sonoran heat ridge and a concurrent Bermuda High, which is mostly a hot pattern below the Canadian border. The presence of a dense Saharan Air Layer and shearing flow aloft argues against tropical cyclone development in most of the Atlantic Basin.

 

Prepared by Meteorologist LARRY COSGROVE on 
Saturday, June 6, 2026 at 11:40 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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