082116 Forecast

Mountain Area Forecast ( August 20-22 )

Showers & Tropical Downpours In Thunderstorms Will Remain Possible Into Sunday.  Much Drier Air & Cooler Temperatures Are Expected Late Sunday Into Monday.

Remain Alert For The Potential Of Strong Rises On Creeks and Ponding Of Water Along Roads And In Typical Low-lying Flood Prone Locations

A significant cold front will be crossing the mountains by late Sunday with showers & downpours in storms possible along and ahead of the front.  Much drier, cooler and refreshing air will be transported into the area Sunday Night into Monday.

Overnight Into Saturday Morning

Chance of a local shower; otherwise, partly to mostly cloudy with areas of fog.  Humid.  Light winds.  Temps in the 60s.

Saturday Afternoon

A chance for showers & thunderstorms.  Winds SSW-SW 5-15 mph, with higher gusts.  Temperatures varying from 60s at highest elevations to the middle 70s to lower 80s.

Saturday Night Into Mid-Morning Sunday

Showers & thunderstorms developing.  Locally heavy rain.  SW winds 5-15 mph, with higher gusts, on mountain ridges and plateaus below 2700 feet.  Winds SW-W at 10-20 mph, with higher gusts, along upper elevation mountain ridges.  Temperatures in the 60s.

Sunday Afternoon

Showers & thunderstorms into mid-late PM ( especially along and south of the High Knob Massif ).  Locally heavy rainfall.  Refreshing air arriving late.  Winds becoming WNW to NW 5-15 mph, with higher gusts.  Temps varying from 60s in upper elevations to the mid-upper 70s.

Sunday Night Into Monday

Mostly clear.  Cooler & refreshing.  Areas of dense valley fog.  Winds WNW-NNW 5-15 mph, with higher gusts, along mid-upper elevation mountain ridges.  Temperatures in the 50s to near 60 degrees ( 50-55 degrees in cooler locations ).

Monday Afternoon

Partly sunny.  Beautiful skies & pleasant.  Winds NW-N at generally less than 10 mph.  Temperatures varying from 60s in upper elevations to the mid-upper 70s.

Cooler mountain valleys, mainly at mid-upper elevations, will drop into the 40s during Monday Night into Tuesday AM ( with somewhat milder low-mid 50s in foggy valleys ).

 

Weather Discussion ( Refreshing Air )

An update near Midnight on Saturday is for a slowing of the cold frontal passage Sunday, with new model runs being a few hours slower to clear the area than yesterday.

Models have also increased rainfall amounts, such that at least localized high water problems could arise.

NAM 12 KM Model Precipitable Water Forecast At 5 PM Sunday
NAM 12 KM Model Precipitable Water Forecast At 5 PM Sunday – August 21
The NAM 12 KM Model has the drier air still just northwest of the Virginia-Kentucky border at 5:00 PM Sunday ( above in brown-blue colors ), with timing being near sunset before it really enters the Cumberland Mountains ( below ).
While this could again made it rough on NASCAR fans, it also means that downpours with a heavy rain potential will linger until deep moisture moves southeast.
NAM 12 KM Model Precipitable Water Forecast At 8 PM Sunday
NAM 12 KM Model Precipitable Water Forecast At 8 PM Sunday – August 21

Given downpours of rain Saturday the potential for strong rises on creeks will need to be monitored, especially if rain becomes heavy and/or prolonged in nature Sunday.  Remain alert for ponding of water along roadways and in typical low-lying, flood prone locations.

The European Model, which did very well with placement of heavier rainfall Saturday, is forecasting the heaviest rains to develop Sunday along the front.  The latest NAM group have trended that way, so please remain alert as at least local high water problems could arise.

 

Previous Discussion

Although humidity, showers & downpours in storms will remain possible ( become likely ) into early Sunday AM, the headline making news is a welcomed push of refreshing air poised to engulf this great mountain landscape from Sunday afternoon into Monday.  It will feel awesome!

University Of Virginia's College At Wise
High Knob Massif  Webcam – University Of Virginia’s College At Wise
A general 1.00″ to 3.00″+ of rain has fallen across the mountain area this week, with frequent hit-miss showers & downpours in thunderstorms and often spectacular tropical skies.
University Of Virginia's College At Wise
High Knob Massif Webcam – University Of Virginia’s College At Wise

August 18-19 featured MAX temperatures in the 70s in Norton-Wise, Sandy Ridge, and Clintwood, with 60s at highest elevations in the High Knob Massif.

*A 78 degree MAX in Clintwood on August 19 will be recorded for the 24-hour period ending at 7:00 AM on August 20 ( below ).
National Weather Service Daily Stats For Clintwood
National Weather Service Daily Stats For Clintwood

Short-range models continue to show the chance for downpours in showers & thunderstorms Saturday into Sunday Morning, especially along-ahead of a cold front  that will finally push away the tropical air and bring simply spectacular conditions to the area for a while.

NAM 4 KM Model Total Rainfall Forecast Into Sunday
NAM 4 KM Model Total Rainfall Forecast Into Sunday

The high resolution NAM 4 KM shows hit-miss downpours, with the NAM 12 KM suggesting best coverage toward the south across the Tennessee Valley & Cumberland Plateau into the TN-NC border area.

NAM 12 KM Model Rainfall Forecast Next 48-Hours
NAM 12 KM Model Rainfall Forecast Next 48-Hours

Regardless of the eventual coverage, cooler and much drier air will sweep across the Mountain Empire from northwest to southeast beginning about mid-morning to mid-day on Sunday.  A most welcomed and long-awaited change.