FXUS63 KUNR 271003 AFDUNR Area Forecast Discussion For Western SD and Northeastern WY National Weather Service Rapid City SD 403 AM MDT Mon Oct 27 2025 .KEY MESSAGES... - Rain and high elevation snow showers today for much of the area. A few rumbles of thunder are also possible across western SD - Drying out for the mid week && .DISCUSSION...(Today Through Sunday) Issued at 402 AM MDT Mon Oct 27 2025 08z upper air analysis shows upper trof axis centered over the Rockies. Lead shortwave is making its way through the CWA with light rain falling across western SD. Rain showers will continue to move through the region this morning as the cold front slowly makes its way across the CWA. Colder air aloft pushes into the region this afternoon with steepening low to mid-level lapse rates as a result. The marginal instability will support chances for a few rumbles of thunder across western SD this afternoon. As colder air arrives, rain will transition to snow across the Black Hills. With the recent warm weather and thus warm ground temps, accumulations should be minimal with perhaps an inch or so of slushy accumulation across the higher elevations. Another wave will skirt the region later this evening into the overnight hours. It looks like the bulk of the forcing will be south of the CWA but a few light snow showers could develop over northeastern WY later this evening. The wave moving through tonight will strengthen and transition to an upper low and dig to the southeast of the CWA. As it does so, weak upper ridging will build into the region for the mid-week bringing drier conditions to the CWA though temperatures will remain seasonable with highs in the upper 40s to 50s. The next system looks to be an upper level wave/low passing to the north of the region late Wed/Thurs. Current guidance isn't showing much moisture associated with this system, with the sensible weather impacts mainly being breezy conditions on Thursday and slightly cooler weather for Friday. && .AVIATION...(For the 06Z TAFS Through 06Z Monday Night) Issued At 1043 PM MDT Sun Oct 26 2025 Clouds will increase tonight, with on and off chances for light rain at the terminal sites through much of Monday. Areas of light snow are possible across the higher elevations of the Black Hills. Areas of MVFR/IFR cigs will also be possible starting in the overnight hours. Conditions will improve Monday afternoon and evening. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...None. WY...None. && $$ DISCUSSION/KEY MESSAGES...Wong AVIATION...Dye