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URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 447
NWS Storm Prediction Center Norman OK
1130 AM EDT Wed Aug 18 2021
The NWS Storm Prediction Center has issued a
* Tornado Watch for portions of
District Of Columbia
central and eastern Pennsylvania
northeast West Virginia
* Effective this Wednesday morning and evening from 1130 AM until
800 PM EDT.
* Primary threats include...
A few tornadoes possible
Isolated damaging wind gusts to 70 mph possible
SUMMARY...Thunderstorms are expected to increase in intensity across
a portion of the Middle Atlantic and Northeast U.S. this afternoon
in association with the remnants of tropical cyclone Fred. Some of
the showers and thunderstorms will become capable of producing a few
tornadoes and isolated damaging wind.
The tornado watch area is approximately along and 100 statute miles
east and west of a line from 20 miles north northeast of
Williamsport PA to 70 miles south southwest of Martinsburg WV. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU7).
REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.
AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 0.5 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 450. Mean
storm motion vector 19035.