365
FXUS63 KUNR 021705
AFDUNR
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1105 AM MDT SUN AUG 2 2026
KEY MESSAGES
-ELEVATED TO CRITICAL FIRE WEATHER CONDITIONS INTO MONDAY
-STRONG COLD FRONT WILL BRING BREEZY WEATHER MONDAY AND MUCH
COOLER CONDITIONS FOR TUESDAY
-MAINLY DRY THIS WEEK
-SMOKE FROM WESTERN WILDFIRES EXPECTED TONIGHT INTO MONDAY
DISCUSSION
(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 1104 AM MDT SUN AUG 2 2026
WESTERN CONUS UPPER RIDGE WILL RETROGRADE AND FLATTEN AS A STRONG
UPPER TROUGH MOVES ACROSS INTERIOR CANADA. A STRONG COLD FRONT
WILL CROSS THE REGION EARLY MONDAY WITH COOLER TEMPS FOR MID WEEK.
HOWEVER, THE RIDGE WILL REBUILD AND SUPPORT HOT WEATHER BY THE
END OF THE WEEK, WITH 90S RETURNING. LEE SIDE TROUGH SETTLING INTO
THE FA WITH WINDS SHIFTING NW ACROSS NW SD AND NORTHEAST WY.
BREEZY SOUTHERLY WINDS WILL PERSIST AHEAD OF THIS TROUGH, ESP SW
THROUGH SCENTRAL SD, CONTINUING THROUGH TONIGHT AS THE LLJ
INTENSIFIES. DRY WEATHER EXPECTED THROUGH MOST OF MONDAY, WITH THE
NEXT CHANCE OF RAIN IN THE FA EXPECTED MONDAY NIGHT INTO TUESDAY
MORNING. MAIN COLD FRONT WILL MOVE THROUGH MONDAY MORNING WITH
WINDS GUSTING OVER 30-40 MPH THROUGH MUCH OF THE DAY ON THE SD
PLAINS. A BATCH OF THICK LOW LEVEL SMOKE FROM OR/WA WILDFIRES IS
EXPECTED TO PUSH THROUGH THE REGION BEHIND THE FRONT TONIGHT INTO
MONDAY PER HRRR/RAP FORECASTS. THIS MAY IMPACT VISIBILITY FOR A
PERIOD, ESP MONDAY MORNING. CONDS WILL IMPROVE MONDAY EVENING AS
THE LL TRAJECTORIES INDICATE A MORE NORTHERLY ORIGIN TO THE
INCOMING AIRMASS. THERE IS A VERY SMALL CHANCE THAT A SHOWER OR
STORM COULD DEVELOP ALONG THE COLD FRONT IN SCENTRAL SD LATE
MONDAY AFTERNOON, BUT LEFT THINGS DRY GIVEN EXPECTED STRONG
CAPPING. STILL COULD SEE A FEW SHOWERS AND TS ACROSS THE SOUTHERN
THIRD LATE MONDAY NIGHT AS THE JET ENTRANCE REGION WILL OVERLAP
WITH A WEAK IMPULSE PASSING TO THE SOUTH OF THE FA, SUPPORTING
ELEVATED CONVECTION. THE BEST CHANCE WILL BE IN SCENTRAL SD WHERE
THE BETTER ELEVATED MOISTURE AND FORCING WILL BE. TEMPS WILL FALL
INTO THE 40S AND 50S MONDAY NIGHT WITH A FEW 30S EXPECTED IN
PORTIONS OF THE HIGHER BLACK HILLS. HIGHS TUES WILL BE 10 TO 15
DEGREES BELOW SEASONAL NORMS MAINLY IN THE 70S, WITH 60S IN THE
BLACK HILLS. WESTERN RIDGE WILL GRADUALLY REBUILD BEHIND THE DEEP
UPPER LOW SLOWLY PUSHING EAST ACROSS INTERIOR CANADA. THIS WILL
SUPPORT A WARM UP WITH INCREASING LL MOISTURE AS SE RETURN FLOW
ENSUES. EXPECT HIGHS TO BE BACK IN THE 90S BY THUR, WITH TRIPLE
DIGITS POSSIBLE BY SAT ON THE SD PLAINS. INCREASING LL MOISTURE
WILL SUPPORT ISOLATED TS CHANCES BY WED AS WEAK IMPULSES WILL
ADVECT THROUGH THE REGION IN NW FLOW. FLOW LOOKS TO BECOME A
LITTLE MORE ACTIVE INTO THE FOLLOWING WEEK (AFTER THE 10TH) AS
SOME OF THE LONGER RANGE MODELS INDICATE A STALLED FRONTAL
BOUNDARY OVER THE REGION WITH FASTER FLOW ALOFT, COMBINED WITH
APPRECIABLE LL MOISTURE.
AVIATION
(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 523 AM MDT SUN AUG 2 2026
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. A FRONT WILL ENTER
THE AREA TODAY WITH WINDS SHIFTING TO NORTHWEST. FRONT WILL STALL
OUT OVER SOUTH CENTRAL SD WITH SOUTHERLY WINDS EXPECTED OVER KICR
THROUGH THE PERIOD.
FIRE WEATHER
ISSUED AT 1104 AM MDT SUN AUG 2 2026
A STRONG COLD FRONT WILL MOVE INTO THE REGION MONDAY. AHEAD OF
THE FRONT BREEZY SOUTHERLY WINDS CAN BE EXPECTED TONIGHT ACROSS
SOUTH CENTRAL SD. NORTH WINDS WILL INCREASE AFTER 9 AM MONDAY
GUSTING TO OVER 30-40 MPH THROUGH MOST OF THE DAY ON THE SD
PLAINS. RELATIVE HUMIDITY WILL DROP INTO UPPER TEENS TO MID 20S
MONDAY AFTERNOON. ALTHOUGH RH'S WILL BE MARGINAL, THE GUSTY WINDS
COMBINED WITH CURED FUELS WILL SUPPORT CRITICAL FIRE WEATHER
CONDITIONS ON MOST OF THE SD PLAINS AND PORTIONS OF THE NORTHEAST
WY PLAINS. A RED FLAG WARNING HAS BEEN ISSUED. WINDS WILL
GRADUALLY DIMINISH MONDAY EVENING WITH A CHANCE FOR SHOWERS AND
THUNDERSTORMS THROUGH THE NIGHT FROM THE BLACK HILLS SOUTH EAST,
BEST CHANCE ACROSS SOUTH CENTRAL SD. MUCH COOLER WEATHER CAN BE
EXPECTED TUESDAY, BEFORE HOT AND MAINLY DRY WEATHER RETURNS LATER
IN THE WEEK.
UNR WATCHES/WARNINGS/ADVISORIES
SD...RED FLAG WARNING FROM 11 AM TO 8 PM MDT MONDAY FOR SDZ322>333.
HEAT ADVISORY UNTIL 8 PM MDT THIS EVENING FOR SDZ013-014-026-027-
030>032-041>044-072>077.
WY...RED FLAG WARNING FROM 11 AM TO 8 PM MDT MONDAY FOR WYZ317.
DISCUSSION...JC
AVIATION...13
FIRE WEATHER...JC
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