Area Forecast Discussion
Issued by NWS Rapid City, SD

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FXUS63 KUNR 250916

Area Forecast Discussion For Western SD and Northeastern WY
National Weather Service Rapid City SD
316 AM MDT WED MAY 25 2016

.SHORT TERM...(Today Through Thursday Night)
Issued at 300 AM MDT Wed May 25 2016

Current surface map shows low across eastern Colorado with trof
extending into central South Dakota. Last of showers exiting
eastern portions of forecast area as upper level shortwave is
lifting into eastern Montana/western North Dakota.

For today, shortwave lifting through the area cuts off across
western North Dakota and consolidates with old upper low along theMontana/Saskatchewan
border. Surface low lifts through central South Dakota late this
morning into early afternoon. This will bring breezy northwest
winds across the western South Dakota plains this afternoon.
Combination of steep lapse rates and marginal moisture gives
MLCAPE of 200-500J/KG across northeast Wyoming into western South
Dakota this afternoon, with up to 1500J/KG across south central
South Dakota. Main threat of severe thunderstorms will be south
and east of the forecast area. Upper low remains across north
Dakota on Thursday. With steep lapse rates, another round of
afternoon and evening thunderstorms expected.

.LONG TERM...(Friday Through Tuesday)
Issued at 300 AM MDT Wed May 25 2016

Persistent upper level troughing over the northwest
CONUS will keep active southwest flow across the Northern Plains
through the Memorial Day weekend. Periodic shortwave energy will
eject out of the trough, keeping a daily chance of showers and
thunderstorms in the forecast through the holiday weekend.
Temperatures will be near seasonal averages, with highs each day
generally in the mid 60s to upper 70s. Lows at night will be in the
40s to mid 50s.


.AVIATION...(For the 12Z TAFS Through 12Z Thursday Morning)
Issued At 300 AM MDT Wed May 25 2016

IFR/MVFR ceilings will be found across northeast
Wyoming, the Black Hills, and into northwest South Dakota this
morning as a weak cold front moves through the area. Showers and
thunderstorms will be possible again today, beginning late this
morning across northeast Wyoming, expanding eastward across western
South Dakota in the afternoon. Best chances for showers and storms
will be from the Interstate 90 corridor north. Outside of the
showers and storms, VFR conditions are expected from late this
morning through Thursday morning, except across higher terrain.


.UNR Watches/Warnings/Advisories...


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