Heavy frost, with a freeze in colder valleys, will occur overnight into this morning. Increasing clouds with development of precip into Saturday morning will prevent frost.
Overnight Into This Morning
Mostly clear. Frosty in mountain valleys. Light winds generally less than 10 mph below 2700 feet. NW-N winds at 10-15 mph, with higher gusts, along upper elevation ridges. Temperatures varying from mid-upper 20s to lower 30s in colder valleys to the upper 30s to low-mid 40s ( mildest along mid elevation ridges and exposed plateaus ).
This Afternoon
Partly to mostly sunny with increasing cloudiness by late. Light NW-N winds generally less than 10 mph. Cool. Temps varying from mid-upper 40s at highest elevations in the High Knob Massif to the middle 50s to lower 60s.
Tonight Into Saturday Morning
Cloudy with a cold rain developing by morning. Winds shifting ENE-ESE at 5-15 mph, with higher gusts, along middle-upper elevation mountain ridges. Temperatures dropping into the 30s to low-mid 40s. Wind chill factors dropping into the 20s & 30s along highest ridges.
Rain will change to snow above 3200 feet elevation by around sunset Saturday, with snow level dropping to 2000-2500 feet by overnight into Sunday. The potential exists for several inches of snow at the highest elevations, with 1″ or less below 3000 feet. Stay tuned for later updates.
Weather Discussion ( March 17-18 )
A frosty start to Thursday occurred in mountain valleys across southwestern Virginia, with a MIN of 32 degrees being observed officially in Clintwood. Temperatures plunged into upper 20s in the coldest valleys to be in contrast with much milder readings along exposed mountain ridges at mid-upper elevations.
A similar setting will develop into this morning ( Friday ) but temperatures will be a few degrees colder in many places, with hard freezes and heavy frost widespread in valleys across Wise and Dickenson counties ( Indian Creek-Pound-Clintwood and the Norton-Tacoma-Coeburn corridors, as examples, will feature nearly continuous frost ( as seen on Thursday AM ).
Yellow Trout Lily Flared Out In Sun-Gusty Winds – March 17, 2016
Bright sunshine prevailed through much of the day before some late afternoon mid to high clouds rolled across. Combined with gusty winds the Trout Lilies were flared out and shaking all day, requiring substantial shutter speeds to stop the motion.
Polypore Fungi With Lichens & Moss In Late PM Light – March 17, 2016
One more nice day for your TGIF should be enjoyed before a nasty Palm Sunday weekend takes shape, with a cold rain developing into Saturday Morning. Saturday looks to be a raw, nasty day with precipitation changing to snow at the upper elevations ( above 3000 feet ) by around sunset.
GFS Model Total Snowfall Forecast ( Thursday AM Run )
Models continue to struggle with amounts and placement, except for general agreement for the bulls-eye of heaviest snow across eastern-northeastern West Virginia and extreme northwestern and northern Virginia ( up to 6″ or more at high elevations ).
GFS Model Total Snowfall Forecast ( Thursday Eve Run )
Locally, across the Mountain Empire, snowfall will be elevation biased with the most accumulations at the highest elevations where there still looks to be a chance for 2-3″+ above 3000 to 4000+ feet during the Saturday Night-Monday AM period.
NAM 12 KM Model Total Snowfall Forecast ( Thursday AM Run )
Even at these highest elevations, some melting will likely occur such that more snow will tend to fall than is ever on the ground at any given time ( given recent anomalous warmth during the past ten days ). Accumulations below 3000 feet will be restricted to night-time and early morning hours.
NAM 12 KM Model Total Snowfall Forecast ( Thursday Eve Run )
The NAM Model group wants to generate the best sticking during Sunday Night into Monday AM at elevations below 3000 feet, as moisture from the Great Lakes comes into the area on WNW to NW upslope flow. Any sticking Saturday Night into Sunday morning being mostly above 3000 feet, with the chance that snow levels will drop to 2000-2500 feet elevation by Sunday Morning.
The above scenario will need to be updated, with a better idea hopefully had by this time tomorrow night.
The Bottom Line – A frosty cold start in mountain valleys this morning will give way to one more nice day before a raw, nasty weekend settles into the mountain region for the Palm Sunday period.
*This includes the official astronomical beginning to spring; however, for climate purposes, Spring 2016 started with the arrival of March ( i.e., Meteorological Spring of March-May ).
Cold rain will develop into the overnight-morning hours of Saturday, with low clouds and wet, raw conditions during the day. It will feel especially chilly in wake of recent anomalously warm days.
Colder air begins overspreading the mountain area by the sunset-Midnight period of Saturday. Any precip lingering will change to snow above 3200 feet during Saturday evening, with snow levels dropping over time into Sunday morning for any moisture left.
Current uncertainty rests with how much moisture will be left for Saturday Night into Sunday morning, and if there may be a break before moisture wraps back into the mountains with Great Lake moisture transport by later Sunday into the early hours of Monday ( before ending ).
Any snow accumulations will be elevation biased, with heaviest amounts most likely above 3000-4000+ feet, with lighter amounts ( generally 1″ or less ) currently expected at elevations below 3000 feet ( mostly amid the 1500-3000 foot zone on the upslope side of the mountain chain with respect to WNW-NW flow ).
Stay tuned for updates, since this system is yet to develop and changes may still occur depending upon numerous factors ( such as storm track-strength ).
Please NOTE that 23 of the past 27 Aprils going back to 1989 have had measurable snow in upper elevations of the High Knob Massif ( before that, 4+ FEET of snow fell in April 1987 ). So please, let no one think this is anomalous. It is still only March!!!
