High Elevation Snow; Blustery Friday
Good morning folks and Happy Thanksgiving! We have a round of light rain and snow moving through this evening, exiting early Friday morning, with sunny skies and cooler temps extending into early next week. A short lived high pressure system will swing through after the frontal passage on Saturday, followed by an upper level trough Sunday into Monday, that will likely stick around through the middle of next week. This upper level trough will lead to uncertainties in the forecast from Sunday through Tuesday, as a piece of energy could swing through our region in the newly established northwest flow at any time, but the models point to a possible round of energy late Sunday and again Tuesday. Temps will be coldest from Sunday into Monday, moderating slowly to near normal levels by late next week. The long range models continue to show above average temps for the month of December, possibly hitting record levels at times, but the overall take home is winter precip chances drop as we enter the last month of the calendar year.
We'll kickoff the timeline Thursday afternoon with temps in the mid - upper 40's above 5000', while the valleys make a run at the low 60's, possibly hitting the low - mid 60's in towns like Bryson City that sit underneath a large mountain range like the Smokies; Sylva and Cherokee also are in play. Clouds build as we approach sunset, with the front arriving shortly after sunset, pushing through shortly after midnight. Most of the region will pick up a tenth of an inch of rain, however the higher elevations above 3500' will see rain kick over to snow closer to midnight, with all snow falling above 5000'. Light snow accumulations around a trace are possible as low as Cowee, Balsam, or Soco Gaps with an inch likely above 5000' by the pre dawn hours. Temps drop to the low - upper 20's overnight and its possible a wet flake or two mixes into the valleys, but the snow level will take till the pre dawn hours to reach the valley floor, just as the precip is scaling back to the the TN line. Alongside rain/snow and crashing temps will be breezy NW winds around 10 - 20mph, gusting to 40mph across the highest ridgelines and peaks.
Clearing skies start the day on Friday and full sunshine is likely by 9 - 10am for all of SW NC, with the immediate TN line holding onto partly cloudy skies till the early afternoon hours. NW flow dominates the day and temps will only make it to the upper 20's - low 30's above 45000' (peaking before noon), while the valleys warm to the mid - upper 40's. NW winds around 10 - 15mph are expected throughout the day. Temps bottom out to the upper teens - mid 20's overnight into Saturday under mostly clear skies; light wind in the valleys, 10 - 15mph above 4000'.
Saturday and Sunday will likely be some of our warmest days this week and next as temps reach the upper 50's across the valleys, while the higher elevations above 4000' hold to the mid 40's. Sunny skies sit overhead Saturday with some minor cirrus mixing in late, while mostly sunny skies Sunday morning give way to partly cloudy skies as we approach sunset. Overnight lows settle into the mid - upper 20's for the valleys Saturday night, with a temperature inversion maintaining temps in the 30's above 4500'; partly cloudy. Sunday night offers up a touch more cloud cover and temps low - upper 20's as cold air advection takes over and forces colder air into the region.
Confidence in the forecast drops beginning Monday, but this is tied to when pieces of energy will round the upper level trough and bring us clouds, precip or gusty winds. For now the models point to a window on Tuesday when this could occur, so the forecast for Monday feels more confident compared to Tuesday. We are going with mostly sunny skies Monday and temps unable to climb past the upper 30's - low 50's depending upon elevation, warming slightly by a few degrees on Tuesday.
We'll stop here and circle back Saturday morning and by then we should have a better handle on the upper level trough (Monday - Wednesday), which are notoriously tough to forecast past 36 hours. Happy Thanksgiving to everyone!