WEATHERAmerica Newsletter; Sunday, April 12, 2026; SHORT RANGE OUTLOOK

[Larry Cosgrove]

SHORT RANGE OUTLOOK

(Through The Next 72 Hours)

 

Tornado Alley Is An Appropriate Term. Along With A Great Deal Of Rain, Hail, And High Winds For The Middle Chamber Of The USA

METEOBLUE

UQAM Meteocentre (3)

TwisterData.Com (3)

University Of Wisconsin Weather Server (4)

PivotalWeather.Com (3)

ECMWF

College Of DuPage Weather Laboratory (2)

Call it "Round One" of prominent severe weather threats across the lower 48 states as we move through the next ten days.

It is always a bad thing when a closed, cold low aloft gets stuck over the Southwest. When the system is kicked out by a digging shortwave or advancing major cyclone/trough, invariably the warm sector of the low center exiting the Desert and Intermountain Regions kicks up a lot of heavy rain and severe weather. This "coming out" process was written in research about a half century ago, detailing major snow potential in the Midwest in winter and tendency for tornado outbreaks in Spring. Acceleration of the system effectively slams cold air, a dry tongue, and vorticity/difluence/shear into a hyper-unstable atmosphere. The greatest "punch" as such will be from north/central Texas and the Heartland through the Corn Belt and Great Lakes before ending across the Mid-Atlantic and Appalachia. The time frame will be from Monday through Wednesday.

Keep in mind that the anchor Southeast ridge will rebuild after the passage of the thunderstorm production, setting up the same boundary position between cool and exceptionally warm and muggy air. This is why chances for a prominent heat wave in Dixie and the Eastern Seaboard will emerge in the medium range, only to be chased out by another powerful storm and trough from the West. Colder air will moderate across Canada but still be a factor in drainage into the USA in the longer term.