Area Forecast Discussion
Issued by NWS Rapid City, SD

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FXUS63 KUNR 230306

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
906 PM MDT FRI JUL 22 2016

Issued at 900 PM MDT Fri Jul 22 2016

Thunderstorms continue to rumble cross the CWA. One batch is
focused on outflow boundaries across central SD. Another batch,
mostly elevated, was located over northeast WY into northwest SD
where low level jet is starting to perk the storms up a bit.
Forecast updated to account for latest timing and trends.


.SHORT TERM...(This Evening Through Saturday Night)
Issued at 234 PM MDT Fri Jul 22 2016

Current surface map shows low over southeast Montana with trof
into the Nebraska Panhandle. Weak shortwave crossing the forecast
area triggering scattered thunderstorms. MLCAPE ranges from around
1000J/kg across northeast Wyoming with 4000+J/kg across northwest
South Dakota. Sufficient shear for a few severe storms, especially
across northwest South Dakota. Bulk of thunderstorm activity will
move east of the forecast area overnight.

Cold front crosses northeast Wyoming and western South Dakota
late tonight...and through south central South Dakota around noon.
Highs 10-15F cooler for Saturday. BL-850mb winds support northwest
winds of 15-30 mph.

.LONG TERM...(Sunday Through Friday)
Issued at 234 PM MDT Fri Jul 22 2016

High pressure over the Dakotas for Sunday. With marginal
moisture...and isolated afternoon thunderstorm is possible over
the Black Hills.

Upper flow will be quasi-zonal Sunday through next Thursday, with
periodic shortwave troughs bringing a daily chance for
thunderstorms. Temperatures will be slightly above average.


.AVIATION...(For the 06Z TAFS Through 06Z Saturday Night)
Issued At 900 PM MDT Fri Jul 22 2016

Isolated to scattered thunderstorms with local IFR conditions
will continue overnight. Late tonight, a strong cold front will
bring gusty northwest winds to the area into Saturday. Outside of
storms, VFR conditions expected.


Issued at 900 PM MDT Fri Jul 22 2016

Temperatures and relative humidities continue to recover this
evening, so the Red Flag Warning has been allowed to expire.

Cold front will cross the area late tonight with gusty northwest
winds for Saturday. Minimum relative humidities will drop below
20 percent for northeast Wyoming and much of western South Dakota
with wind sufficient for the continuation of the Fire Weather


.UNR Watches/Warnings/Advisories...
SD...Fire Weather Watch from Saturday afternoon through Saturday
     evening for SDZ260>262-264.

WY...Fire Weather Watch from Saturday afternoon through Saturday
     evening for WYZ259-297>299.



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