Area Forecast Discussion
Issued by NWS Rapid City, SD
Issued by NWS Rapid City, SD
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613 FXUS63 KUNR 251629 AFDUNR Area Forecast Discussion For Western SD and Northeastern WY National Weather Service Rapid City SD 1029 AM MDT Tue Jun 25 2024 .KEY MESSAGES... - Warm with isolated thunderstorms today and Wednesday. - Better chance of thunderstorms on Thursday with increasing severe thunderstorm potential && .DISCUSSION...(Today Through Monday) Issued at 225 AM MDT Tue Jun 25 2024 Current surface map places weak high across the western Dakotas. East-west line of thunderstorms continue is located from north of the Black Hills into central South Dakota in area of 750-600mb theta-e advection. This thunderstorm activity lingers through early morning with a gradual decrease in coverage and intensity. Later this afternoon/evening, shortwave slides through eastern Montana into North Dakota. Residual low level moisture and steep lapse rates across the area, with MLCAPE around 2000J/KG. Some question as to thunderstorm coverage as best forcing remains north of the forecast area and robust cap in place, especially east of the Black Hills. CAMs pop up a few storms this afternoon/evening, with higher probabilities around the Black Hills and along weak front sliding through. Sufficient shear to support severe hail threat. Surface high drops across the area tonight/early Wednesday, with drier boundary layer across the forecast area, shunting best buoyancy south of the forecast area. Impulse tracking through flat ridge may be enough to bring a few high based storms across northeastern Wyoming/Black Hills area Wednesday afternoon. Thunderstorm coverage increases Wednesday evening/overnight on nose of level jet/theta-e advection. Strong shortwave moves through the northern Rockies into the Plains late Thursday with surface low/cold traversing the western Dakotas. Buoyancy/shear favorable for all modes of severe weather Thursday afternoon/evening. Temperatures cool down for Friday/Saturday with lingering shower/thunderstorm activity. && .AVIATION...(For the 18Z TAFS Through 18Z Wednesday) Issued At 1028 AM MDT Tue Jun 25 2024 Isolated thunderstorms are expected to develop this afternoon, mainly over western SD. Severe storms are possible. Besides any brief MVFR conditions near storms, VFR conditions will continue through the TAF period. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...None. WY...None. && $$ DISCUSSION/KEY MESSAGES...7 AVIATION...Pojorlie