WEATHERAmerica Newsletter, Saturday, July 19, 2025; SHORT RANGE OUTLOOK

[Larry Cosgrove]

SHORT RANGE OUTLOOK

(Through The Next 72 Hours)

 

Monsoonal Moisture Moves Out Of Texas And Into The Desert And Intermountain Regions

METEOBLUE

UQAM Meteocentre (3)

TwisterData.Com (3)

University Of Wisconsin Weather Server (3)

College Of DuPage Weather Laboratory

Texas and the south central states have had their fill of extreme rainfall amounts and severe weather. But the attached precipitation chart reveals a new scenario: no serious rainfall as subsidence returns sunshine, hot and dry weather with high surface relative humidity. We are likely to see intense convection in discrete or linear fashion over the northern High Plains and Prairie Provinces in the near term, with a general east-southeast progression into the Great Lakes, Mid-Atlantic and New England states. There may be a brief cool intrusion into sections of the Midwest and Northeast behind the first two impulses. Watch for microbursts, with the main danger zone alonga  Rapid City SD....Des Moines IA....Cincinnati OH arc initially. Communities closer to the Canadian Border will have the strongest impacts by later in the new week as the heat ridge strengthens near Texarkana TX.

Heat Ridge Expansion In Great Plains And Mississippi Valley

METEOBLUE

PivotalWeather.Com (3)

ECMWF

The initial, and likely longest-lasting surge of high heat will be over Texas, the Great Plains and Mississippi Valley in the near term. Starting out as a singular 500MB ridge over Dixie, expansion will force a merger with the Bermuda High while also forcing the Mexican moisture fetch associated with the monsoon to occupy the Desert and Intermountain Regions. Keep in mind that once entrenched in the West, diurnal + orographic thunderstorm chances will peak in mid-August and not entirely leave the area left of the Continental Divide until the second week of September.

This is going to stick around for a while, folks: Unstable West, Hot Central, Changeable East. A "Ring Of Fire" thunderstorm formation around the big heat ridge!