SNOWFALL MAP – FIRST CALL (TUESDAY)
A low pressure system will move across the Tennessee River Valley and into the Mid-Atlantic on Tuesday. Cold air in place Tuesday morning will precipitation to be in the form of snow across Southwestern Virginia, Shenandoah Valley, and portions of the Virginia Piedmont.
While this is a quick moving system, the low pressure area is expected to intensify off the Mid-Atlantic coast. This could mean a few inches of snow for portions of the Delmarva Peninsula (mainly north of Salisbury, Maryland.)
The timing of precipitation still needs to be worked out. However, in many cases, precipitation tends to start earlier than what models indicate. This will also be an overrunning event and precipitation can develop well ahead of the system.
Temperatures Monday night will fall into the mid 20’s across Southwest Virginia, with upper 20’s across the Virginia Piedmont. This will help cool the ground and I am not worried about the ground being “too warm” for no accumulation. Also, we don’t have a strong sun angle to worry about in January. We are at the time of winter where the single angle is at it’s lowest (January and February.)
TUESDAY 4 AM to 10 AM
On the latest GFS American model (and afternoon European model,) snow will likely develop across far Southwestern Virginia before sunrise, then slowly move into the New River and Roanoke Valley by 7 to 9 a.m. With cold air in place and bursts of snow, I could see where this area receives a quick 1 to 3 inches, with locally higher amounts possible.
By mid-morning, snow will move into the Southern Piedmont, including Martinsville, Danville, and the Lynchburg area, with temperatures in the upper 20’s to near 30 degrees.
Any snow that falls through 10:00 a.m. will could accumulate on roads (including primary roads,) especially if it comes down in heavier bursts. Bridges, overpasses, and untreated roads will have the greatest chance of seeing slick conditions.
TUESDAY 10 AM to 4 PM
Once we head into late morning and into mid-afternoon, snow will move into the Virginia Piedmont, Central and Northern Shenandoah Valley, and Northern Virginia. Temperatures will slowly rise into the lower 30’s, and roads may be just wet by this point. However, snow accumulation on elevated surfaces and grass appears likely at this point. Bridges and overpasses and less-traveled roads will likely experience slick spots.
TUESDAY 4 PM to 9 PM
By Tuesday evening, low pressure will be off the Mid-Atlantic coast and will interact with energy to the north, across the Great Lakes and the Northeast. This could intensify the area of low pressure and we could see a few inches of snow across portions of the Delmarva Peninsula.
SNOWFALL – FIRST CALL
Wherever the area of low pressure tracks, main dynamics and lift will be just to the north and west. At this time, this is favored across Southwestern Virginia — This area could see a few to several inches of snow, depending on timing. If it arrives earlier with the colder air around, it will tend to be more of a drier snow. This includes the New River and Roanoke Valley, Central Shenandoah Valley, and portions of the Virginia Piedmont.
As the system moves east, it will begin to weaken somewhat. However, some accumulation of an inch (or two,) will be possible across Northern Virginia and Central Maryland. The “wildcard” is the strengthening of the low pressure system off the coast and “when” it happens. This will determine what – if any – accumulations will occur across the Delmarva Peninsula, northward into Southeastern Pennsylvania and New Jersey.