Tuesday Evening (2/10) Weather Discussion

(Posted 5:30pm)

By now, everyone should know that big time cold is on the way later this week.  Wednesday is our last "warm" day before our big time cold down.  Temperatures will plummet throughout the day Thursday with the passage of the first cold front. Highs will struggle to make the freezing mark Friday and Saturday with night time lows dropping well into the teens. A reinforcing shot of severe arctic air will arrive Saturday night with lows dipping well into the single digits across western Virginia. Highs might not even make it out of the teens in the Shenandoah Valley Sunday before flirting with the 0 degree mark Sunday night.  Keep in mind most of this period will consist of gusty northwesterly winds so wind chills will be a good 10-20 degrees colder at times. Start making preparations now for frozen pipes, outdoor animals, etc.   

departure from average temperatures for Sunday...anywhere from 10-25 degrees below avg. across the east

Although limited in moisture, both cold blasts will also bring upslope snow showers to the western facing slopes.  The ski resorts of West Virginia will really cash in by the time things are all said and done early next week.  As always, a few flurries or scattered snow showers may make it over the mountains during either of these...but I'm particularly interested in the Thursday system for a few snow squalls to bleed over into parts of Virginia.  The NAM indicates very steep low level (surface to 850 mb) lapse rates exceeding 10-12 deg C/km accompanied by strong 500 mb positive vorticity advection (PVA) shown below...both very conducive for this potential.  Once again, the limiting factor will be the amount of moisture but it doesn't take much for this kind of setup. These are often very isolated in nature so not everyone will see them...those that do can expect brief bursts of snow (the kind where it's sunny one minute and white out the next) with ground coatings possible.

500 mb vorticity Thursday