131
FXUS63 KUNR 022308
AFDUNR
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
508 PM MDT WED SEP 2 2026
KEY MESSAGES
- ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS PORTIONS OF
NORTHEASTERN WYOMING AND SOUTHWESTERN SOUTH DAKOTA THIS EVENING.
GUSTY WINDS WILL BE POSSIBLE.
- ABOVE AVERAGE TEMPERATURES WILL RETURN FOR THE SECOND HALF OF
THE WEEK. THE WARMEST DAYS WILL BE FRIDAY AND SATURDAY WITH
HIGHS IN THE MID TO UPPER 90S.
- ELEVATED TO NEAR-CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
THROUGH SATURDAY.
DISCUSSION
(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 146 PM MDT WED SEP 2 2026
UPPER AIR ANALYSIS SHOWS RIDGING OVER THE OHIO VALLEY, WITH THE MAIN
AXIS JUST CROSSING INTO THE EASTERN DAKOTAS. A STRONG UPPER LOW JUST
OFFSHORE THE PACIFIC NW COAST IS BRINGING ACTIVE SOUTHWESTERLY FLOW
TO MUCH OF THE WESTERN CONUS, INCLUDING THE CWA. A SHORTWAVE IS
CROSSING WY AT THIS TIME, WITH ISOLATED SHOWERS AND THUNDERSTORMS
DEVELOPING OVER THE LAST TWO HOURS. SURFACE OBS (AND EVEN THE KUDX
RADAR) SHOW NICELY A WARM FRONT PUSHING INTO THE BLACK HILLS AND
SOUTHERNS SD. TEMPERATURES HAVE RISEN INTO THE 90S BEHIND THE FRONT,
ALONG WITH DEWPOINTS DROPPING FROM THE 60S OVER THE WESTERN SD
PLAINS INTO THE 40S. THIS FRONT WILL CONTINUE NORTHEASTWARD THROUGH
MOST OF THE CWA BY LATE EVENING. STORMS MAY MAKE IT INTO THE
CWA...ESPECIALLY THE SW PORTIONS. BECAUSE OF THE DRIER AIR MOVING
IN, INSTABILITY IS RATHER WEAK. HOWEVER, INVERTED BOUNDARY LAYER
PROFILES BEHIND THE FRONT WOULD SUPPORT GUSTY WINDS. IF STORMS MAKE
IT ACROSS THE CWA BORDER, CAN'T RULE OUT SOME GUSTS MAKING IT ABOVE
50 MPH (AS HAS ALREADY OCCURRED IN THE CYS CWA). WHILE
INSTABILITY IS MUCH HIGHER AHEAD OF THE WARM FRONT, SO IS THE
CAP...SO STORMS ARE NOT EXPECTED TO BE AN ISSUE TOWARD NW SD. THE
WARMER, DRIER AIR WILL CONTINUE TO ADVECT IN THROUGH THURSDAY
MORNING. HIGHS WILL REACH INTO THE UPPER 80S AND 90S WITH MOSTLY
SUNNY SKIES. A SECOND REINFORCING SHOT OF HOT, DRY AIR WILL BE
DRAWN INTO THE CWA FRIDAY MORNING AHEAD OF A STRENGTHENING SURFACE
LOW OVER MT. TEMPS WELL INTO THE 90S...AND EVEN NEARING 100...ARE
POSSIBLE FRI AND SAT. AFTER SATURDAY, MODELS DIVERGE WITH WHAT
NEXT WEEK WILL LOOK LIKE. THE SPREAD OF SOLUTIONS GENERALLY RANGE
FROM NEAR AVERAGE TO WELL ABOVE. CLIMATOLOGICALLY, EARLY TO MID
SEPTEMBER TENDS TO BRING A NOTICEABLE SHIFT TOWARD COOLER, MORE
AUTUMN-LIKE (AKA MILD) WEATHER. BOTH THE 12Z GFS AND ECMWF ARE
FINALLY HINTING AT THIS WITH A COLD FRONT PUSHING THROUGH DURING
THE FIRST HALF OF NEXT WEEK. WILL BE INTERESTING TO SEE WHERE
MODELS SETTLE OVER THE NEXT FEW DAYS.
AVIATION
(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 507 PM MDT WED SEP 2 2026
GUSTY SOUTHWESTERLY WINDS WILL CONTINUE TO DIMINISH THIS EVENING.
ISOLATED SHOWERS AND THUNDERSTORMS ARE POSSIBLE OVER NORTHEAST
WYOMING AND WESTERN SOUTH DAKOTA THROUGH 03/05Z. TRANSIENT MVFR
CONDITIONS ARE POSSIBLE AROUND ANY HEAVIER PRECIPITATION CORES AND
GUSTY/ERRATIC WINDS CAN BE EXPECTED WITH ANY STRONGER CONVECTIVE
CORES. VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD OUTSIDE
OF ANY SHOWERS/THUNDERSTORMS.
FIRE WEATHER
ISSUED AT 146 PM MDT WED SEP 2 2026
WARMER AND MUCH DRIER AIR IS MOVING INTO THE NORTHEASTERN WY AND
SOUTHWESTERN SD AND WILL CONTINUE ACROSS THE REST OF WESTERN SOUTH
DAKOTA THIS EVENING. TEMPERATURES WILL INCREASE THROUGH THE REST
OF THE WEEK WITH HIGHS WELL INTO THE 90S. VERY DRY HUMIDITY IS
ALSO EXPECTED, DROPPING TO NEAR OR BELOW 15 PERCENT ACROSS
NORTHEASTERN WY AND PORTIONS OF FAR WESTERN SD. WITH SOUTHWESTERLY
WINDS GUSTING UP TO 30 MPH EXPECTED THURSDAY AFTERNOON, HAVE
ISSUED A RED FLAG WARNING FOR CAMPBELL AND MOST OF WESTON COUNTY
IN NE WY. ELEVATED TO NEAR-CRITICAL FIRE WEATHER CONDITIONS ARE
EXPECTED ELSEWHERE THROUGH SATURDAY.
UNR WATCHES/WARNINGS/ADVISORIES
SD...NONE.
WY...RED FLAG WARNING FROM NOON TO 8 PM MDT THURSDAY FOR WYZ314-315-
317.
DISCUSSION...13
AVIATION...SCHULTZ
FIRE WEATHER...13
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page