WEATHERAmerica Newsletter, Saturday, April 6, 2024; MEDIUM RANGE OUTLOOK

[Larry Cosgrove]

MEDIUM RANGE OUTLOOK

(Four To Ten Days From Now)

 

Another, Larger, Stronger Storm Moves Through The West Into The Great Plains

UQAM Meteocentre (4)

TwisterData.Com (4)

PivotalWeather.com (4)

College Of DuPage Weather Laboratory (2)

It will take a while before we lose the storm that forms over Texas and Oklahoma on Monday. Embedded in a longwave trough complex, and somewhat impeded by a heat ridge complex covering the Caribbean and Sargasso Seas, the disturbance and its attendant frontal structure will produce multiple rounds of intense thunderstorms across Dixie and the Eastern Seaboard. Missing from the precipitation type will be snow, which will be reduced to some locations in the leeshores of the Great Lakes by Thursday and Friday.

A new storm will emerge first over the Gulf of Alaska, then move into the West Coast. Again, this feature will be part of a full-latitude trough with a polar air mass. Snowfall in the West will be mostly limited to higher elevations. But the slow eastward progression of the disturbance will increase snowpack in the various ranges of the Intermountain Region. Thunderstorms will emerge as the main threat, along with a strong surface wind over the Great Plains by next weekend.

Warm West Vs. Cool Central Vs. Warm East Alignment Slowly Takes Shape (With Trough/Storm In The Middle)

ECMWF (4)

TrueWx.Com (4)

As suggested above, the slow motion of the storm and trough complex will mean that it will take a while for any change in the temperature array across North America. The nature of an mP regime crossing into the Great Plains and Mississippi Valley means that rather than truly cold, the nature of this storm will be for only small drops in temperature in the middle chamber of the continent. There may be some snow in Saskatchewan and Manitoba by April 16. But a warm-up will get underway both to the left and the right of the system. Asw we move into the longer term, the question will be, "does the system weaken and lift up into Canada?" At some point, the subtropical high in the Greater Antilles will begin its northward advance and introduce hot weather to the southern and eastern rim of the nation. Just not in April, most likely.