WEATHERAmerica Newsletter; Saturday, January 17, 2026; EXTENDED PERIOD FORECAST

[Larry Cosgrove]

EXTENDED PERIOD FORECAST

(Between Day 11 And Day 15)

 

A Wild, Wintry Weather Pattern Possible Through February

CIMSS (2)

NOHRSC (2)

TropicalTidbits.Com (Dr. Levi Cowan) (3)

NOAA/PMEL

NOAA/CPC

HPRCC (2)

Environment Canada

WeatherBell (9)

The January Thaw signature across the lower 48 states is crumbling. The formation and position of a James Bay vortex almost always implies bitterly cold air from the Rocky Mountains to the Gulf and Atlantic coastlines. A southern branch storm track deriving energy and moisture from the Madden-Julian Oscillation moves through northern Mexico into the warm Gulf waters, creating opportunities for cold advection and frozen precipitation. And the vast snow cover stretching from Eurasia across the North Pole into North America will help chill the atmosphere while enabling additional snow and ice development. This sounds like a near-perfect scenario for an active second half of January until the first week of March.

While things can go wrong in the forecast set-ups (we are still feeling the results of that data cut-back from lost rawinsondes....). Most of the numerical models have dumped earlier projections for widespread warmth in the lower 48 states this winter. The analog system has performed remarkably well, even projecting the extremely cold negative 500MB height anomaly passing through Akimiski Island coming up around January 28. Temperatures are already turning colder, while the +PNA ridge, albeit in somewhat muted form, has been dominant in the West. The general idea that model guidance has shown repeatedly is a warm West vs. cold Central/East alignment.

Aside from the minor "starved" shortwaves tracking around the big gyre around James Bay, all that seems to matter is for the large storm and moisture fetch off of western Canada to eject a disturbance along the frontal structure below the Rio Grande Valley and on into the neck of Florida. I urge caution while following the forecast, simply because tight snow/ice/rain division may emerge in areas that do not often see any frozen precipitation. And because some bitterly cold air will increase heating demand like crazy between now and February 15. This will not be an easy forecast period, trust me.

 

Prepared by Meteorologist LARRY COSGROVE on 
Sunday, January 18, 2026 at 3:10 P.M. CT

Disclaimer: 
The previous statements are my opinions only, and should not be construed as definitive fact. Links provided on this newsletter are not affiliated with WEATHERAmerica and the publisher is not responsible for content posted or associated with those sites.

Copyright 2026 by Larry Cosgrove

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