ACTIVE AND LOADED WITH VARIETY...
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ACTIVE AND FULL OF VARIETY
An energetic northwest flow pattern has brought many of us periods of light snow (even some freezing drizzle) going back to last Saturday. Another weak disturbance may bring some patchy flurries or freezing drizzle early Tuesday but it doesn't have much for dynamics to work with. In some areas it will pass entirely un-noticed.
The next one follows fast on its heels later today bringing another shot of light snow, especially for the northeast half of my area (particularly NE of a line from near Waterloo to Clinton and to the east of Princeton, Illinois. This little clipper has a bit more fortitude but it's moving so fast the snow band should last no longer than 2-4 hours in any one spot. As a result, most areas that get into that limited snow burst should see 1/2 to 1inch of accumulation. Where the lift is maximized there may be a narrow channel 10-15 miles wide where 1-2" totals materialize. The hi-res models are hinting at that possibility. You can really see it on the 3k NAM where that thin blue line is draped out through NE Iowa into NW Illinois.
The EURO is a little less aggressive but very much in line with the heaviest band in the same general area.
The bottom line is this shouldn't be much more than a nuisance in the north and nothing more than a few flurries in the south. Once it departs the weather stays quiet over the central Midwest until the second half of the weekend.
Temperatures which have been on the cold side and in the 20s since Sunday will moderate, especially Wednesday and Thursday when some low 40s are possible south of HWY34. The rest of the area gets above freezing but the existing snow pack will hinder the warm-up. Wednesday is likely to be the warmest day with highs that look like this on the ERUO.
Thursday night a cold front surges south and it means business considering it contains some legitimate polar air. Temperatures will fall during the day and by early afternoon Friday wind chills are shown falling into the range of 5 below to 5 above.
Friday night with fair skies, light wind and snow cover in most areas, temperatures should free-fall and we are setting up for what could be the coldest night of the winter so far. The EURO shows below zero lows all the way to I-80.
Return flow commences Saturday as the cold core of the high moves off to the east. That means warm advection sets in bringing clouds and some snow back to the forecast for Saturday night and parts of Sunday. In the south half of my area, mainly HWY 30 south there could be some issues with precipitation type and that might mean some freezing rain, (or south of HWY 34 a complete transition to rain).
Models are still attempting to resolve the strength of the energy and how it ejects from a southwestern trough. It does look like a series of impulses are possible and that could make for an active period early next week with snow north and snow or rain south. This graphic from the NWS shows the risk for moderate snowfall greatest north of I-80.
Taking it one step at a time is the prudent way to go and I'll leave it this way. The system Saturday night and Sunday has the potential to lay down 1-3" totals, with the northern half of my area (HWY 30 north) most favored for the higher amounts. Here's some of the early projections for snow which again is very preliminary and nothing to bank on. Right now we are just trying to ascertain the trends.
The Canadian GEM
That will do it for now. Until we meet again roll weather...TS