NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION. Privacy and Cookie policy

FXUS61 KRNK 101846 AFDRNK

Area Forecast Discussion National Weather Service Blacksburg VA 146 PM EST Sun Dec 10 2023

SYNOPSIS
A strong cold front will move exit the piedmont this evening, shifting off the coast Monday morning. High pressure covers the Mid Atlantic region Monday night through Friday, providing dry weather and moderating temperatures.

NEAR TERM /THROUGH MONDAY/
As of 119 PM EST Sunday...

Key Messages:

- Advisory remains in effect for snow across the mountains of WV, far SW VA and NW NC. A dusting to 2 inches further east, but locally higher amounts at the highest elevations along the Blue Ridge Parkway possible.

- Heavy rain with low potential for severe weather threat remains in the Piedmont this afternoon

- Winds behind the front tonight into Monday morning will be blustery but not quite advisory levels.

Watching convection moving north from the NC piedmont toward southside VA. The stronger storms have been further southeast over the Triangle area in NC, but forecast models showing potential increase in bulk shear toward southside VA into Caswell County early this afternoon, so will have to watch for potential strong winds/isolated tornado.

As far as hydro issues, overall the rain has been welcome though some areas have received over 2 inches of rain since early this morning. Where much of this occurred in the west, the flooding threat seems to be diminishing here, but the piedmont will have to watched with the convection, and in the urban areas as street flooding may occur. Feel that creeks, streams and mainstem rivers will see some rises, for most part they will stay well within their banks.

The next issue is watching the transition from liquid to frozen as the cold air comes in with the upper shortwave. Mesoanalysis at 18z showed 8h 0C isotherm from near Charleston, WV to Jackson KY to Crossville TN. Models bring the colder air to the mountains by 00z, then driving it east over the piedmont after midnight. Cold air changes the rain to snow, but will be a window of 1-2 hours and with warm ground layer will have to rely on rates to bring accumulations to a level for advisory outside the mountains. But as we head through the night into Monday morning will likely see some slick roads as far east as Lynchburg. At this time, no advisory and will take one more look later this afternoon, as at least a Special Weather Statement should be issued. Think the piedmont will also see snow, and thinking is the rates would have to be heavy enough to accumulate on roads, but warm/wet ground expected to melt this as temperatures at dawn should still be in the lower to mid 30s across the piedmont. Still some grassy surfaces/cars and rooftops will have a dusting.

Further west, and with the snow showers with the upper trough snow amounts are going to range from a dusting to 1 inch in the valleys to 2 to 5 inches in the higher elevations, with locally higher in the mountains of western Greenbrier County, WV. Also the higher ridges along the Blue Ridge Parkway, like Apple Orchard, Peaks of Otter and Buffalo Mountain should see as much as 2-4 inches.

Finally, the wind. Models show two surges of wind gusts, one this evening with the cold air advection behind the front, then again shortly after sunrise Monday with behind the upper shortwave with good pressure rises. Model soundings and local wind study suggest sub-advisory levels. Exception may be the higher terrain along the NC/far SW VA counties. This already is embedded in the winter weather advisory as this advisory encompasses the time of the winds.

As the upper trough exits Monday will see snow showers taper to flurries before ending by midday in the mountains. Could see flurries across the WV mtns through early afternoon, as clouds linger longer.

Sunshine returns to piedmont in the morning, reaching the Blue Ridge and New River valley by noon. Despite this a cold airmass will keep highs about 5-10 degrees below normal with mid 40s in the piedmont, to 30s in the mountains, with 20s at the higher elevations.

Forecast confidence is moderate on rain/snow totals and where advisory is. Confidence is higher on temperatures, sky cover and winds. Low confidence on flooding/severe threat.



SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/
As of 830 AM EST Sunday...

Confidence is high for dry weather.

High pressure will build across the Mid Atlantic on Monday night, which will bring drier weather and lighter winds. Temperatures should plummet into the teens and 20s by Tuesday morning due to the more ideal radiational cooling. The upper flow pattern flattens and becomes zonal later on Tuesday, so temperatures should moderate closer to normal values for this time of year by Wednesday. An upper level trough should pass to the north during late Wednesday into Wednesday night, but dry air across the Appalachian Mountains will keep this forecast period free of any precipitation.

LONG TERM /THURSDAY THROUGH SUNDAY/
As of 830 AM EST Sunday...

Confidence is moderate for dry weather through Friday, but there may be a chance of precipitation towards the weekend.

Dry weather will continue for Thursday and Friday due to strong surface high pressure. The models have remained quite consistent with the overall pattern through this work week, but that consistency breaks down on Saturday as they are struggling to discern an area of low pressure developing along the Gulf Coast.
Some models keep this developing low pressure system to the south during the weekend, but others are allowing the system to track northeastward along the East Coast. For now, just a low chance of precipitation has been inserted into the forecast for late Saturday into Sunday, but confidence is very low on what could happen until better model agreement is obtained in future runs.

AVIATION /18Z SUNDAY THROUGH FRIDAY/
As of 1242 PM EST Sunday...

Aviation conditions will vary this afternoon but in general will be poor flying weather with periods of rain, heavy at times along/east of LYH/DAN, with a few embedded thunderstorms possible along/southeast of DAN.

Ceilings and vsbys have been fluctuating from IFR or lower to VFR.

A front moves east later this afternoon winds turn west and pick up late this afternoon into this evening. Rain showers turn to snow showers this evening at BLF/LWB, reaching ROA/BCB by 04z, then LYH and even DAN could have snow after 06z for a limited time. While this is occurring cigs/vsbys will be MVFR to IFR.

Should see improving conditions east of the mountain after 12z Monday, reaching BCB by 18z. Wind from the northwest to continue to be gusty in the 15-25kt range, higher in the ridges of the Blue Ridge.

Extended Aviation Discussion...

High pressure will bring return to VFR for all after 21z Monday and persist this way into the rest of the week. Cannot rule out some fog Tuesday morning in the river valleys.

RNK WATCHES/WARNINGS/ADVISORIES
VA...Winter Weather Advisory from 7 PM this evening to 1 PM EST Monday for VAZ007-009-015.
NC...Winter Weather Advisory from 7 PM this evening to 1 PM EST Monday for NCZ001-018.
WV...Winter Weather Advisory from 7 PM this evening to 1 PM EST Monday for WVZ042-043-508.

toggle option: (graph/table)

Full Color Weather Map

Link to Loop




Other links: GEOS-West     Contential US     Full GOES-East

Blacksburg, VA,