567 FXUS63 KUNR 161722 AFDUNR Area Forecast Discussion For Western SD and Northeastern WY National Weather Service Rapid City SD 1122 AM MDT Thu May 16 2024 .KEY MESSAGES... - Unsettle pattern continues through the period - Warm Friday. Late day thunderstorms with cold front could bring some locally strong wind gusts. && .DISCUSSION...(Today Through Wednesday) Issued at 147 AM MDT Thu May 16 2024 Current surface map places weak trough across the western Dakotas. Weak shortwave moving through the area is producing a few light rain showers over southeastern Montana. The showers will clip far northwestern South Dakota early this morning. Second shortwave arrives later today with isolated showers/thunderstorms over the Black Hills and northwestern South Dakota. For Friday, stronger upper trough moves through the Northern Plains. Low level thermal ridge peaks, with highs reaching the upper 70s to upper 80s. Surface trough pushes through Friday afternoon with deeper boundary layer moisture in central/eastern South Dakota. Lack of buoyancy will initially limit thunderstorm development to Black Hills Friday afternoon. Better chance of thunderstorms comes with increasing mid level forcing and cold frontal passage. Front arrives in northeastern Wyoming and northwestern South Dakota late afternoon and moves through the rest of western South Dakota Friday evening. 3-5mb/3hr pressure rises will bring a period of gusty northwest winds with the cold front. Enhanced downdrafts with thunderstorms may produce some locally strong winds. In wake of the upper trough, Saturday will be cooler and breezy. Next upper trough will bring showers and thunderstorms Sunday/Monday, followed by another for the middle of the week. && .AVIATION...(For the 18Z TAFS Through 18Z Friday) Issued At 1122 AM MDT Thu May 16 2024 Isolated showers will be possible this afternoon and evening across portions of the western SD plains. Other than any brief MVFR conditions near any precipitation, VFR conditions are expected through the TAF period. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...None. WY...None. && $$ DISCUSSION/KEY MESSAGES...7 AVIATION...Dye