Sunrise 5:21 AM   Sunset 8:16 PM Moonrise 2:32 PM   Moonset 2:57 AM

  Print   HELP   Reset   Save   Recall  New

FXUS63 KUNR 180052 AFDUNR

Area Forecast Discussion For Western SD and Northeastern WY National Weather Service Rapid City SD 652 PM MDT Fri May 17 2024

KEY MESSAGES

- Cold front this evening with gusty northwest winds.

- Strong to severe thunderstorms late this afternoon and evening across northwestern South Dakota with the main threat damaging wind gusts.

- Unsettled pattern continues through much of next week.

UPDATE
Issued at 649 PM MDT Fri May 17 2024

Thunderstorms have weakened, so have canceled the Severe Thunderstorm Watch. Northwesterly winds are becoming strong behind the cold front, and will remain strong overnight.

UPDATE Issued at 355 PM MDT Fri May 17 2024

With the cold front already entering far northwest SD, will start the wind advisory now for that area.

DISCUSSION
(Today Through Thursday)
Issued at 222 AM MDT Fri May 17 2024

Water vapor shows upper low over the Northern Rockies with short wave ejecting into eastern MT. At the surface, cold front extends from far northwest ND through southeast MT. Temps in the warm sector across our area early this afternoon area well into the 70s/80s. Skies are mostly clear across our area, but thunderstorms are developing along the cold front over southeast MT.

Later this afternoon and evening, robust cold front will cross our western zones and should be all but through our far south-central SD zones by midnight. Showers/storms will continue to develop along the front this afternoon as it sweeps southeast. MLCAPE in the 500-1000J/kg range and inverted-v soundings will support high based thunderstorms with a damaging wind threat, mainly north of the Black Hills, into early evening, with activity shifting east of the forecast area by later tonight. In addition, pressure rises behind the front in the 3-6mb/3hr range will support a period of very gusty northwest winds, which may also aid the severe gust potential with thunderstorms. Current wind advisory looks good.

Dry, cooler, and breezy conditions expected Saturday. Next shortwave impacts the area late Sunday with a chance of showers and thunderstorms. Upper trough lingers across the Pacific Northwest/Northern Rockies through much of next week with a series of impulses crossing the area. This will result in daily chances for showers and thunderstorms and temperatures near seasonal averages.

AVIATION
(For the 00Z TAFS Through 00Z Saturday Evening)
Issued At 425 PM MDT Fri May 17 2024

A strong cold front will continue to move across the CWA tonight, behind which there will be strong northwesterly winds (gusts up to 45 kts) across northwestern SD tonight. Thunderstorms have developed along the cold front and will shift into central SD early this evening; these storms are producing strong wind gusts as well (over 50 kts). Another round of showers could move through northwestern SD overnight. MVFR conditions will be possible in any showers/storms; otherwise, VFR conditions are expected through the TAF period. Skies will clear on Saturday morning, and winds will decrease through the day.

UNR WATCHES/WARNINGS/ADVISORIES
SD...Wind Advisory until 3 AM MDT Saturday for SDZ001-002-012>014-025- 026-031-032-072-073-078.
WY...None.

Full Color Weather Map

Link to Loop


Other links: GEOS-West     Contential US     Full GOES-East

Rapid City, SD,