011017 Forecast

Mountain Area Forecast ( Jan 10-12 )

An ALERT Continues For Strong SSW-SW Winds Into Thursday, With Strongest Winds Expected At Middle To Upper Elevations During Much Of This Period.

A prolonged period of very windy conditions, with high wind gusts, will be impacting the Cumberland Mountains during the Tuesday to Thursday period ( January 10-12 ).  Despite milder air working into the area, these strong winds will continue to make conditions feel cold Tuesday & chilly through Wednesday.  The strongest winds are expected to come in waves, centered on the daylight and evening hours of Tuesday as well as the Wednesday afternoon into Thursday time period.
**As moisture increases dense fog will become widespread at the highest elevations.  This will also need to be watched for at middle and lower elevations, especially within the SW Upslope Flow zone from Wise-Sandy Ridge plateaus southwest across the High Knob Massif into portions of Lee County ( and locally in other locations ) during the Wednesday-Thursday period.

Tuesday Night Into Wednesday Morning

Cloudy & windy.  A chance of evening showers, then rain developing into the overnight.  Wind driven across higher elevations.  Local downpours in the SW upslope zone.  SSW to SW winds 10-25 mph, with higher gusts, along mountain ridges-plateaus below 2700 feet.  SSW-SW winds 20-35 mph, with higher gusts, along mountain ridges above 2700 feet.  A period of lower wind speeds into predawn hours ( then increasing again after sunrise ).  Temperatures mainly in the 30s to lower-middle 40s.  Wind chills in the 20s & 30s, except 10s highest ridges ( evening ).  Areas of dense fog developing into the overnight-morning.

*As milder, moist air comes into contact with cold, frozen ground the potential for dense fog formation will arise by the overnight-Wednesday period.  Dense fog formation is also more likely within the SW upslope flow zone where air is forced to naturally rise.  Caution Is Advised.

Wednesday Afternoon

 Windy with showers likely.  Downpours possible.  Areas of dense fog, especially in the SW air flow upslope zone.  S-SW winds 10-25 mph, with higher gusts, on mountain ridges and plateaus below 2700 feet.  Winds SW 20-35 mph, with higher gusts, on mountain ridges above 2700 feet.  Temps widespread in the lower 40s to low 50s ( warmest at the lower elevations in the downslope zone from Pound to Clintwood, Haysi & Grundy ).

Wednesday Night Into Thursday Morning

Chance of showers & drizzle.  Areas of dense fog.  Windy.  SSW-SW winds 10-25 mph, with higher gusts, on mountain ridges-plateaus below 2700 feet.  SW winds 20-35 mph, with higher gusts, along mountain ridges above 2700 feet.  Temperatures widespread in the 40s.

A mild & wet pattern is expected during the next 5-10 days, with a heavy rainfall potential continuing to be monitored for next week.  Stay tuned for updates.

 

Weather Discussion ( Windy-Wet )

Wednesday Afternoon Update

Following a very windy Tuesday, with cold wind chills, a boundary that produced showers, local downpours, and light rain-fog changed wind directions and temporarily reduced wind speeds for a more pleasant Wednesday PM. Cloud bases even lifted briefly off all but highest peaks.

High Knob Massif Webcam – University Of Virginia’s College At Wise

Cloud bases are lowering and winds are increasing once again as the sun is setting on this Wednesday.

Lonesome Pine Airport In Wise
Temperatures reached lower 50s at UVA-Wise through 4:00 PM, with low-middle 40s observed in upper elevations where a morning period featured wind speeds mostly under 25 mph.  This as the strongest winds are coming in waves, as predicted, with the next period of ROARING winds already underway at higher elevations.
Black Mountain Mesonet – Updated To 6:10 PM Wednesday – January 11, 2017
*The warming nature of the atmosphere can be seen as temps at high elevations are just reaching their highest levels now, as the sun is setting ( the warmest temps observed since January 3 ).

Due to another period with a tightening pressure gradient I will keep my ALERT for strong S to SW winds into Thursday for middle-upper elevations of the Cumberland Mountains.  Many limbs have been blown out, so caution is advised. 

 

Previous Discussion

In my opinion it was a cold Tuesday. Even though temps are rising WIND was a major factor at middle-upper elevations amid the Cumberland Mountains, with 15-30 MPH sustained speeds from Wise upward in elevation ( gusts 40-50+ mph at higher elevations within the High Knob Massif, Black-Pine mountains ).  That made conditions feels like 20s-30s in Wise and 10s & 20s at upper elevations above 3000 feet.

High Knob Massif Webcam – University Of Virginia’s College At Wise
Wind chills have consistently been in the 20s and 30s throughout Tuesday in Wise, even with Lonesome Pine Airport’s 1-2 degree F warm bias ( versus UVA-Wise and other local thermometers ).
Lonesome Pine Airport In Wise
Wind speeds only get stronger the higher in elevation you venture.
Flatwoods Mountain Mesonet
At 5:00 PM temperatures were the warmest of the day at highest elevations, and the warmest since last week, with low-mid 30s at upper elevations from the High Knob Massif to Black Mountain.
Black Mountain Mesonet
Snow remains solid, significant, and roads partially or completely covered in upper elevations of the High Knob Massif where winds sound like a JET taking off.  I still have some doubts if I will be able to take my Field Studies In Microclimatology class on a field trip into upper elevations by this weekend!  Time will tell.
Eagle Knob of High Knob Massif At 4:48 PM Tuesday – January 10, 2017
ECMWF Ensembles 51-Member MEAN 500 MB Height Anomalies: Days 1-5

Although a boundary with colder air will bear watching by Friday into this weekend ( first along western slopes of the Appalachians then down along the eastern slopes ) a much warmer pattern is clearly going to dominate most of the USA during the next 5-10 days.  This will also be a wetter pattern, with amounts needing to be monitored over time.

ECMWF Ensembles 51-Member MEAN 500 MB Height Anomalies: Days 6-10

Periods of rain are expected, as many waves moves across the region amid fast flow aloft.  Due to the combination of both Pacific Ocean moisture ( at mid-high altitudes ) and Gulf of Mexico moisture ( at low-levels ) amounts over time could become significant.  This is what the synoptic pattern is saying versus any particular model.  Stay tuned.

ECMWF Ensembles 51-Member MEAN 850 MB Temp Anomalies: Days 1-5

The mean temperature during the next week to 10+ days will average well above “normal” for this time of year.

European Ensembles 51-Member MEAN 850 MB Temp Anomalies: Days 6-10

There are longer range signs, with expected changes within the stratosphere, that suggest a wintry pattern will return by late January into February.  More harsh weather ahead?  Time will tell amid a winter season that can not yet lock down into any given temperature regime, with wetness being the only consistent theme.