ALERT For The Potential Of Excessive Rainfall Into This Weekend
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More than 2.00″ of rain fell in the Pound area of northern Wise County (2.28″ measured in Pound Gap near U.S. 23) late Wednesday, beneath slow moving thunderstorms.
Heavy rain potential will continue through this upcoming weekend, with excessive local rain amounts being likely.
This is part of a stormy, late summer pattern that is expected to continue through the next one to two weeks (reference increasing upper air trough formation over the eastern USA on these mean, 51-member European Model forecasts).
Derecho Recap_10 August 2020
An event that sparked my interest in weather as just a kid was associated with a gustnado that formed along an outflow boundary. I have been interested in these types of events ever since. The following links highlight what will be recorded as a historic Derecho event.
At least 10 Million acres of corn in Iowa alone, were destroyed by a classic Derecho that blasted across the Midwest on 10 August 2020.
This is estimated to represent more than 1 Billion bushels of corn and a loss of at least 3.4 Billion dollars (just in Iowa). This Derecho impacted more than 800 miles of varied landscapes, much of it in the nation’s heartland.
The peak recorded wind gust reached 112 mph in Cedar Rapids, Iowa.
Inside The Iowa Derecho_Nick Stewart (KGAN-TV)
Corn can be seen in a portion of Nick’s video, as part of a live broadcast associated with KGAN-TV during the event. A link to the full broadcast is below:
KGAN-TV_Rebecca Kopeland and Nick Stewart
The Derecho remained a potent force through Illinois, as it turned southward toward the Ohio River before weakening below severe limits.
Andrew Pritchard_Storm Chaser_In Illinois
NOAA highlights a GOES-16 visible loop of the Derecho, with lightning overlain.
GOES Watches Derecho Slam Midwest_NOAA
Derecho Definition And Facts_Storm Prediction Center
A long-lived wind damage producing system of organized, severe thunderstorms will approach the Appalachians overnight.
Interactive Storm Reports_NOAA-NWS
At this time, weakening is expected, however, this must be closely monitored and a severe potential will exist until it is seen that the system dissipates upstream of the local mountains. A right turn into most unstable, energy-rich air toward western and central Kentucky is likely.
Wind damage often continues as the system weakens with a downward transfer of high momentum air to the surface, such, that I include this in the term “dissipates” that extends somewhat beyond disappearance of stronger radar echoes.
It appears that locations toward Cumberland Gap will be at higher risk, versus locations to the north and east, but please stay tuned to NOAA weather radio and your favorite media sources for updates on this evolving situation.
Interactive Full-Screen Doppler Radar
Rounds of showers and downpours in thunderstorms will impact the mountain region through this week into the upcoming weekend.
Interactive Lightning And Storm Tracking Doppler
Showers and thunderstorms Monday will initially impact southwestern portions of the region, with a general east to northeast expansion of the impact zone from Tuesday into mid-late week.
While the placement of heaviest rain varies on nearly every model run, the idea of locally heavy to excessive amounts in localized places is what needs to be monitored.
Development of upper-air troughing over the eastern USA, in combination with a break in the heat ridge across the Deep South, will support increasing chances for showers & downpours in thunderstorms through mid-late week.