ALERT For Strong SSE-SSW Winds Developing During Wednesday Night Into Thursday – Especially At Middle To Upper Elevations
Heavy frost with a hard freeze will occur in mountain valleys overnight into this morning. Low temperatures within the 20s to low 30s will be common in mountain valleys. Exposed mountain ridges-plateaus will remain frost free as winds increase at high elevations and mix downward to middle elevation ridges during the overnight into this morning.
Overnight Into This Morning
Mostly clear ( some high clouds possible ). Large vertical temperature spread developing between colder valleys and milder mountain ridges. SSE to SSW winds increasing into the overnight to 10-20 mph, with higher gusts, on exposed mid-upper elevation mountain ridges. Temps varying from frosty 20s to lower 30s in colder valleys ( with calm winds ) to the 40s on milder, exposed mountain ridges.
This Afternoon
A mix of sun and high clouds. Warmer. SSE winds 10-20 mph, with higher gusts. Temperatures varying from 50s amid upper elevations in the High Knob Massif to the low 70s in downslope locations ( mid-upper 60s Norton-Wise ).
Tonight Into Thursday Morning
Increasing clouds. Windy across mid-upper elevations. SSE-S winds 10 to 25 mph, with higher gusts, on middle elevation mountain ridges and plateaus below 2700 feet. Winds S-SW 20-30 mph, with 40+ mph gusts, on mountain ridges above 2700 feet. Temperatures in the 40s to lower-middle 50s ( coolest in valleys with light winds and along highest mountain ridges ).
Showers and thunderstorms, with possible downpours, will become likely during Thursday. Waves of rain could produce heavy rainfall amounts during the Thursday-Saturday period. Stay tuned for updates on this developing storm system.
Weather Discussion ( March 29-30 )
Upslope clouds into predawn hours of Tuesday broke enough for some frost to form in colder locations as temperatures dropped into the 30s.
Eastern Redbud ( Cercis canadensis ) Along State Route 83
A seasonably chilly Tuesday featured abundant sunshine and beautiful blue skies. Afternoon temperatures varied from 40s across upper elevations, above 3000 feet, to lower-middle 50s in Norton-Wise and upper 50s in Pound-Clintwood.
Close Up View of Eastern Redbud – Along State Route 83
The day ended with dry air and a nice sunset.
High Knob Massif Webcam – University Of Virginia’s College At Wise
This set the stage for a large vertical temperature spread to develop tonight, with 1:00 AM temps at 32 degrees or lower amid colder valleys verses low-mid 40s on exposed middle-upper elevation mountain ridges.
Black Mountain MesoNET Up To 1:30 AM Wednesday – Elevation 4031 Feet
Increasing winds along mid-upper elevation mountain ridges overnight will mix downward across the entire area today, with strong wind speeds developing by tonight into Thursday as the pressure gradient tightens up ahead of the next storm system.
Flatwoods Mountain MesoNET Up To 1:30 AM Wednesday – Elevation 2774 Feet
Following a much drier than average March, the potential for the first heavy precipitation ( rainfall ) event since the middle-end of February is on tap for the Thursday-Saturday period; although, variations of rain amounts are substantial depending upon the forecast model. So questions remain as to what “basin-average” amounts will be. Local variations are likely with any convection ( i.e., thunderstorms ).
*A factor on the side of the NAM, at least from a low-level forcing perspective, is the strong S-SW wind field that will be developing to enhance orographics. Thus, heavy rain will be likely IF moisture transport into the area is not limited by upstream convection.
NAM 12 KM Model Total Rainfall Forecast To 8 AM Saturday – April 2
The NAM Model group is much heavier with rainfall amounts than the U.S. GFS Model. Given the recent tendency for dryness during March this will be interesting to see which model verifies.
GFS Model Total Rainfall Forecast To 8 AM Saturday – April 2
The convective pattern will also be a factor, and is difficult to predict accurately in advance, with strong-severe storms currently expected west and south of the Appalachians that could influence moisture transport into the mountains.
Storm Prediction Center Severe Risk Regions To 8 AM Thursday
An enhanced risk for severe thunderstorms, with possible tornadoes, over the already water logged lower Mississippi Valley favors the lower rain numbers of the GFS-European models into Friday for the mountains. However, this will need to be updated as the actual rain-storms develop.
Storm Prediction Center Severe Risk Regions To 8 AM Friday
Stay tuned for updates as new model runs come out today.
