Hit-Miss Tropical Downpours & Thunderstorms Will Continue This Weekend Into Next Week With A Threat For Localized Water Problems In A Jungle-like Air Mass
A jungle-like high water content air mass will continue to grip the mountain region through coming days. Heavy to locally excessive rainfall will be possible in places amid a hit or miss pattern.
Remain alert if heavy rain develops over or upstream of your location. Stay tuned to NOAA Weather Radio and your favorite media sources for possible warnings or advisories.
Overnight Into Saturday Morning
Areas of dense fog. Chance of a shower or downpour in a thunderstorm, especially toward morning. SW-WSW winds 5-10 mph along mid-upper elevation mountain ridges. Humid with temperatures mostly in the 60s.
Saturday Afternoon
Chance of hit-miss showers & downpours in thunderstorms. SW to W winds 5-10 mph on mid-upper elevation mountain ridges & plateaus. Humid with temperatures varying from lower 70s at highest elevations to lower 80s ( warmer south toward the Great Valley and Tri-Cities and below 1500 feet ).
Saturday Night Into Sunday Morning
Chance of hit-miss showers & downpours in thunderstorms. Areas of dense fog. SW-W winds 5-10 mph along mid-upper elevation mountain ridges. Humid with temperatures in the 60s to around 70 degrees.
Sunday Afternoon
Chance of hit-miss showers & downpours in thunderstorms. SW to W winds 5-10 mph on mid-upper elevation mountain ridges & plateaus. Humid with temperatures varying from lower 70s at highest elevations to lower 80s ( warmer south toward the Great Valley and Tri-Cities and below 1500 feet ).
Sunday Night Into Monday Morning
Chance of hit-miss showers & downpours in thunderstorms. Areas of dense fog. WSW-WNW winds 5-10 mph along mid-upper elevation mountain ridges. Humid with temps in the 60s to around 70 degrees.
Monday Afternoon
Chance of hit-miss showers & downpours in thunderstorms. SW to W winds 5-10 mph on mid-upper elevation mountain ridges & plateaus. Humid with temperatures varying from lower 70s at highest elevations to lower 80s ( warmer south toward the Great Valley and Tri-Cities and below 1500 feet ).
Weather Discussion ( July 26-August 1 )
The mountain landscape of the Cumberland Mountains has turned into a jungle, in wake of a general 5.00″ to 10.00″ of July rainfall, and like a jungle this will force a carbon copy forecast featuring a daily chance for hit or miss showers and tropical downpours.
High Knob Massif Webcam – University Of Virginia’s College At Wise
Although many dry hours will be observed through coming days, the pattern of hit or miss downpours will continue as a humid air mass and wet landscape combine to generate abundant moisture for occasional development of showers and thunderstorms. While most of these will be non-flash flood producers, the risk for a local cloud burst must continue to be respected.
While day-time heating will favor the most activity, night-time heavy rains can not be ruled out at this time of year in a pattern that has now developed ( via progressive wetness and positive feedback for rainfall production above wetter terrain features ).
High Knob Massif Webcam – University Of Virginia’s College At Wise
Atmospheric heights increase again into next week but not to the extent observed during mid-late July, with a similar positioning of the heat dome suggesting a continuation of steamy air with occasional showers and thunderstorms.
European 51-Member Ensemble MEAN 500 MB Height Forecast – DAYS 1 to 5
Heights increase some in the upcoming 5-10 day period as the air mass heats and the atmosphere undergoes vertical expansion in a persistent WNW-NW type of flow field.
European 51-Member Ensembles MEAN 500 MB Height Forecast – DAYS 6 to 10
Climatology shows that mean rainfall tends to undergo a decrease from July into August, on average, as noted here:
July To August MEAN Rainfall Trend
Big Cherry Lake Dam
7.05″ to 5.76″
Wise
5.30″ to 4.05″
Clintwood
4.75″ to 3.65″
During any given year; however, this may not hold true with persistence patterns like this making things more complicated as activity fires chaotically over wet terrain.
Ironically some are needing rain, especially south of the Cumberland Mountains, with all regions tending to have large variations in rainfall over short distances.
USA Drought Monitor As Of July 26, 2016
Wetness has clearly beat out dryness from the High Knob Massif northward, even though the level at Big Cherry Lake remains less than average due to release of large amounts of water during the past 4 weeks or so to augment flow on the Powell River that has been running into drier terrain within northern Tennessee.
