The Mid-Atlantic Daily Snow

Snow & Powder Forecasts for Mid-Atlantic

Thursday, December 20, 2012 7:35am MST

Daily Snow One Sentence Summary: Winter finally arriving tomorrow with showers changing to snow by morning over the highlands with 8-12 inches of snow likely along with prime snowmaking conditions.

Forecast finally looks good for local areas! Showers this evening will increase in intensity overnight in advance of a cold front advancing through the area tomorrow morning. By early morning Friday, areas in WV, MD, and Western PA could be experiencing blizzard conditions with winds gusting over 50 mph and temperatures plummeting into the low twenty’s or teens by noon. Anyone making planning to drive into WV, Garret County MD, or Western PA from Friday through Saturday should be prepared for heavy snow and whiteout conditions. Seven Springs, Wisp, Canaan, Hidden Valley, Ttimbeline, Whitegrass, and Snowshoe should all pick up at least 8 inches with a foot or more possible.

Despite the windy conditions, I expect the snow guns to be on throughout the region by early tomorrow evening and run 24 hours per day through Monday and possibly into Tuesday. One exception will be the areas closer to DC where daytime temperatures may be too warm to allow round the clock snowmaking. Combining snowmaking and natural snow, I expect areas at elevation (Wisp, 7 Springs, Hidden Valley, Ttimberline, Canaan Valley, Snowshoe, and Wintergreen) will have top to bottom runs open by Monday. Lower elevation areas will have a tougher task in front of them given daytime temperatures will go above freezing and may limit their window for snowmaking; it's possible that some areas will be able to open limited terrain by Christmas is temperatures cooperate

Looking forward, wet weather may again come into the picture sometime around Christmas day with temperatures moderating before we go back into another period of cooler weather (possibly longer and colder). I’ll post a more detailed Christmas Week forecast tomorrow.

Weather Fact: Some of you may be interested as to why it will be snowing over the higher elevations of WV, MD, and PA on Saturday but perfectly sunny over the mountains of VA and around DC. The forcing mechanism for the snow this weekend is what we call “Upslope” which occurs when moist air, moving quickly, runs into elevated terrain, is lifted up, and cools to the point where water vapor condenses to form clouds then precipitation. In this case, after the front moves through, winds howling out of the west will create an upslope situation over the highlands, lasting through Saturday, and the precipitation will fall as heavy snow in a localized area and mainly at higher elevations.