*UPDATE*………Complete Information On Major Storm’s Impact On UsDecember 19th, 2012 at 1:24 pm by Chad Evans under Chad's WLFI Weather Blog
Have upped wind gusts in our northwest counties for late Thursday-Thursday night based on 18z model run showing better potential of gusts to 55 mph there.
There is no good warm air advection yet into the area (warm air coming in). Thermometer sits at 42.0 degrees as of 2:39 p.m. at WLFI with just a very light east-southeast wind. It appears this warmth will not arrive until after dusk. So, we will hit our high for the day after dusk as temperatures rise.
OVERNIGHT-EARLY THURSDAY MORNING…………..
Overnight, temperatures will rise as this warm air is funneled in ahead of that major storm with southeast & south winds increasing. We will hit our high temperature for tomorrow in the morning at near 54. Some scattered showers & perhaps a few t’storms will arrive overnight.
Tonight-Thursday will feature showers & a few t’storms arriving overnight-early, early in the morning with the main rain band with a few embedded t’storms passing Thursday morning. This will likely be a squall line of severe t’storms from parts of Illinois, down to Arkansas, but not so here. An overnight-mornign rain-wrapped tornado will be possible (with pockets of damaging straight-line wind) will be possible from Illinois southward to Arkansas.
It looks like more of a squally rain band here. It does not look warm or unstable enough for severe threat, despite screaming wind fields & dynamics. If it were 60 or 62 in the morning, it would be a different story.
This band will pass & the rain may tend to shut off a bit as the strong cold front approaches & passes with the rapidly, re-intensifying surface low near Chicago.
THURSDAY AFTERNOON-EVENING & OVERNIGHT………….
The Arctic front will blast through & the winds will howl with falling temperatures. A few showers will go to snow in the evening with wind-driven snow showers & howling winds through the evening & into the night.
Even with near 1″ of snow, it will still blow around across roads & the 1-3″ farther north will blow, making for low visibility. Winds may gust 45-50 mph.
Winds will still gust to 45 mph early Friday morning, bringing windchills down to -6 at times. Friday itself will feature clouds & some sun with winds gusting 30-40 mph & temperatures only in the 20s. Some flurries/few snow showers will be possible, while some lake effect snow showers will continue in our northeastern & eastern counties.
10-20″ of snow will fall Iowa to Wisconsin with gusts to 60 mph possible. There, white-out conditions will develop tonight & last through Thursday night. Blizzard Warnings are up from Colorado to Wisconsin.