WEATHERAmerica Newsletter, Saturday, July 13, 2024; SHORT RANGE OUTLOOK

[Larry Cosgrove]

SHORT RANGE OUTLOOK

(Through The Next 72 Hours)

 

Heat, Humidity Still Rule Much Of The Lower 48 States....

METEOBLUE

PivotalWeather.Com (3)

ECMWF

This being mid-July, heat is still going to have the upper hand even with thunderstorm chances and higher cloud cover. The interconnected heat ridge complex (Sonoran + Bermudan) will be a main feature in the near term, and will only show marked decline at midweek. Convection associated with the onset of the monsoonal fetch from Mexico is already appart in portions of the Desert and Intermountain Regions, and a splinter effect from the southwestern USA ridge will induce some extremely high temperatures in the Great Plains over the following 72 hours. Then there's the matter of that cold front developing in Manitoba and western Ontario....

....While A 500MB Cold Pool And Surface Front (With Thunderstorms) Make A Move South From Central Canada

METEOBLUE

TwisterData.Com (3)

University Of Wisconsin Weather Server (3)

UQAM Meteocentre (3)

College Of DuPage Weather Laboratory

You may notice some extremely unstable air across the north central states that begins to drift, then accelerate, south and east toward the Midwest and Great Lakes. A cold pool much like what was seen with the Beryl circulation last weekend will proceed into Kansas and the western Ohio Valley within 84 hours. Enough vorticity, diffluence and surface convergence is present to generate something akin to a tornado outbreak from the Dakotas all the way through the Heartland and eastern Corn Belt, and quite possibly involving Appalachia and the Mid-Atlantic as the polar air mass starts to reach lower latitudes. The monsoonal fetch in Mexico could also have an influence within the high heat in the West in this period.