Area Forecast Discussion
Issued by NWS Rapid City, SD
Issued by NWS Rapid City, SD
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378 FXUS63 KUNR 060944 AFDUNR Area Forecast Discussion For Western SD and Northeastern WY National Weather Service Rapid City SD 344 AM MDT Mon May 6 2024 .KEY MESSAGES... -Very windy with a slight chance of stronger thunderstorms today. -Very strong winds possible tonight and Tues across northeast WY, the Black Hills, and northwest SD. -Unsettled and cool through mid week, then slowly warming. && .DISCUSSION...(Today Through Sunday) Issued at 311 AM MDT Mon May 6 2024 09Z upper level analysis has strong closed low over southwest WY with 110kt jet rounding the base of the main trof. Showers and isolated storms are lifting north across the area at the moment. At the surface, low pressure is located across southeast WY with in inverted trof extending into eastern MT. Strong southeast winds are present across the forecast area, with temperatures in the 50s. Vigorous and complex system will affect the area for the next several days, as the upper low lifts across western SD, pinwheels through western ND, then finally shifts southeast by mid week. Cool and unsettled conditions, along with a lot of wind, will be the main weather story for the next several days. On the precip side of things, surface low pressure and associated trof will swing northeast across the area today. Along the trof, a few stronger storms are expected early this afternoon to the north and east of the Black Hills. Modest CAPE, good shear, and low level helicity could produce an isolated tornado with these storms. Threat is short lived as the trof shifts quickly northeast by late afternoon. More widespread rains will impact northeastern WY, the western portions of the Black Hills, and northwestern SD, as abundant moisture wraps around the backside of the low. Some light snow will be possible across the higher elevations of the Black Hills tonight into Tuesday night. On the wind side of things, very windy conditions are expected with this very dynamic system. West to southwest winds will increase again today as the surface trof swings north of the area. Have issued a Wind Advisory for much of the SD plains starting at noon today with winds persisting into the evening. As the surface low and upper low become stacked tonight, winds could increase even more across parts of northeastern WY, the Black Hills, and northwestern SD. A High Wind Watch remains in affect for this evening into Tuesday. Precip chances decrease on Tuesday as the system spins across western ND, but very windy conditions will persist across western SD, especially far northwest SD where Warning criteria winds will be possible. Upper low finally starts to weaken on Wednesday, as it tracks back southeast across central and eastern SD. Windy conditions will persist along with chances for showers and isolated thunder. Drier and less windy conditions will slowly work back into the area late Thursday into Friday as weak high pressure slides into the area from the northwest. Temperatures will climb back into the 60s for Friday and Saturday, with some 70s returning for Sunday. && .AVIATION...(For the 06Z TAFS Through 06Z Monday Night) Issued At 1058 PM MDT Sun May 5 2024 Scattered showers and thunderstorms are possible overnight, from east of KGCC into the western SD plains. MFVR/IFR conditions are possible with any stronger cores. Moist, upslope flow has resulted in MVFR ceilings developing across the Black Hills into KRAP; these will persist through much of the forecast period. Additional showers and storms are possible after 10-12z Monday morning, spreading eastward throughout the day. Winds will shift out of the west-northwest throughout the day Monday, with gusts 35-50 knots possible by early afternoon through the late evening hours. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...Wind Advisory from noon today to 11 PM MDT this evening for SDZ001-002-012>014-026-027-030>032-041>043-073>075-078. High Wind Watch from this evening through Tuesday afternoon for SDZ001-012-013-025-072-073-078. Wind Advisory until 11 PM MDT /midnight CDT/ this evening for SDZ044-046-047-049-076-077. WY...High Wind Watch from this evening through Tuesday afternoon for WYZ060. && $$ DISCUSSION/KEY MESSAGES...15 AVIATION...SE