Widespread high impact weather to close July primarily centered on an excessive heat event centered on the Mid-south U.S. but forecast to expand through early August. Previously, the mid-August forecast was trending less hot. But overnight, another hot spike appeared in the East U.S. according to the GFS model.

Beginning yesterday, forecast models indicated potential evolution of a tropical system east of New Jersey. Water temperatures support tropical development (81-82F). Additionally, a very hot 11-15-day forecast from recent days is suddenly cooler into the Midwest according to GFS and AIFS.

While Saharan Dust has suppressed tropical cyclone activity for much of July, the mid-troposphere is quite wet and supports a buoyant tropical cyclone season ahead once the Saharan Dust issue eases likely by the middle third of August.

The U.S. population weight CDD forecast explodes to well above normal August 2-8. The GFS is the hottest model, but all ensembles are trending hotter. Contributing to the increasing CDD during early August are hotter forecasts in the PJM-East sector.