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I wish I had $10 for every blog post I've ever had to write about borderline ice threats the past few years. Well, this is another. First off, there is LOTS of moisture expected to stream northeastward ... to the tune of 2-3 inches of rain across the area through Wednesday evening.  (Linked map courtesy of Hydrometeorological Prediction Center) If all of this were likely to be ice, we would be in a world of hurt by  Wednesday morning. The tricky part for forecasters over the next 24-36 hours will be figuring out what percentage of this amount is likely to be sleet or freezing rain. Eventually, with the low pressure system moving northeastward to our west, sweeping in mild air aloft, and the high pressure system supplying cold air slipping off the East Coast near Washington DC, it appears almost certain that a good chunk of this rain will fall with temperatures above freezing. On the front end, though, it all depends on how much cold air can be held in as the first waves of moisture arrive late Monday night and Tuesday. In the inset map, the HPC has determined that most of Western Virginia carries a slight risk of getting .25 inch of ice accretion Tuesday (the blue outlined area) while the region from Roanoke north to Winchester (generally the Shenandoah Valley) has a moderate risk of doing so.  (Full map linked here) The trick is figuring out where, whether and if it will get to freezing as rain is falling, and secondly, how long it will stay that cold while the rain falls. Right now, the expectation is for some scattered light freezing rain and sleet late Monday night and Tuesday, changing to rain during the afternoon and early evening, with most of the rain falling AFTER it gets above freezing. If the cold air holds in just a little longer, things could get a little more serious. But it seems like the pieces are a bit out of place for a major winter storm, especially the positioning of the high pressure system pushing in the cold air. It's expected to be near D.C.; it would need to be in central Pennsylvania or New York for a better angle at keeping the cold air wedged in as warm, moist air overrides it.

This will all seem crazy tonight and Monday, as lows tonight fail to hit 40 and highs on Monday might even challenge 60 if there is some sun. But colder air is due to arrive Monday night before the moisture arrives.

Behind this storm it will get windy and cold with the typical mountain snow showers Wednesday and beyond. I am keeping an eye on a disturbance Thursday night that forecast models have been consistent in swinging through from the northwest. That could enhance the snow for a period of time, maybe even to the point of some accumulations.