A BIG WIND DRIVEN CHANGE...
PLEASE HELP ME MEET MY FUNDRASING GOALS...
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A WIND DRIVEN CHANGE...
Slowly but surely, a stiff southwest wind brought a spring like air mass into the Midwest Wednesday. By late afternoon highs surged into the 50s across my entire area. Even in Minnesota and Wisconsin where up to two feet of snow was on the ground highs f 35 to 40 were common. The really good stuff was out in the central Plains where highs in the 70s were noted.
The most significant warming took place from my area west where highs were 15-20 degrees warmer than Tuesday.
The warm up was spearheaded by a developing low pressure in Colorado. Note the packing of the isobars ahead of the system. That resulted in gusty south winds which continue to blow early Thursday. As a result, the day gets off to a mild start with temperatures near 40 at daybreak.
By then, moisture return has reached significant levels with water vapor exceeding an inch all the way to I-80 at noon.
That will be the fuel for rain and showers that surge into the south shortly after daybreak and then work there way north into the rest of the region by early afternoon. Here's what the surface map is projected to look like 1:00 PM Thursday afternoon. A surface low is tracking northeast along a cold front extending from SC Iowa into SE Minnesota.
That means we are still on the mild side of the system. With clouds and precipitation around that will hinder readings from getting overly warm but mid 40s to mid 50s should show up from I-80 south. The north won't be as fortunate where low 40s are indicated.
Conditions go downhill rapidly towards evening when the surface wave is projected to be be near Burlington. Winds will have turned to the north bringing sharply colder temperatures into my Iowa counties. Rain has or is changing to snow showers in central Iowa.
At midnight the surface low has progressed north of Chicago and the GFS shows strong north winds over all the area and a narrow fast moving band of light snow progressing out of eastern Iowa into western Illinois.
Models are showing some light accumulations in spots, generally less than an inch. That's a hard call due to how long precipitation continues once the transition to cold and snow occurs. In most areas it should happen quickly leaving little time for accumulation. To me, my counties NW of the Quad Cities would have the best chance of seeing up to an inch of snow but that would probably be confined to a narrow swath. I expect most spots probably don't see much more than a dusting if current trends hold. This is a situation where we'll just have to watch how things unfold Thursday morning and adjust from there...what's known as nowcasting. Here's what models are currently suggesting for accumulations. I'll start with the official NWS forecast.
The odds of an inch or more.
Now to model guidance. These are not forecasts, just raw model output that forecasts are comprised off.
The GFS
The EURO
The Canadian GEM, by far the most bullish for snow and an outlier.
The 3k NAM
Precipitation totals are generally light to moderate, 1/4 to 1/2 inch. Models indicate this.