154  
FXUS63 KFSD 270346  
AFDFSD  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SIOUX FALLS SD  
1046 PM CDT TUE AUG 26 2025  
   
KEY MESSAGES
 
 
- TODAY WILL BE THE LAST FALL LIKE DAY WITH TEMPERATURES WARMING  
TO NEAR SEASONABLE FOR WEDNESDAY AND THURSDAY.  
 
- ADDITIONAL CHANCES FOR RAIN RETURN TONIGHT AFTER MIDNIGHT  
TONIGHT AND PERSIST THROUGH WEDNESDAY. SOME STRONGER STORMS  
ARE POSSIBLE WEDNESDAY AFTERNOON WITH THE POTENTIAL FOR SMALL  
HAIL AND GUSTY WINDS.  
 
- MORE WIDESPREAD RAIN CHANCES AND COOLER CONDITIONS RETURN BY  
FRIDAY NIGHT THROUGH THE UPCOMING HOLIDAY WEEKEND. DETAILS CAN  
STILL CHANGE HEADING INTO THE WEEKEND SO PLEASE CONTINUE TO  
MONITOR THE LATEST FORECAST FOR THE MOST UP TO DATE  
INFORMATION.  
 

 
   
DISCUSSION
 
 
ISSUED AT 250 PM CDT TUE AUG 26 2025  
 
QUIET CONDITIONS PERSIST THIS AFTERNOON. HIGH TEMPERATURES HAVE  
WARMED A BIT MORE TO THE 70S WHILE WINDS REMAIN LIGHT OUT OF THE  
SOUTH/SOUTHEAST. TODAY WILL BE OUR LAST FALL LIKE DAY SO GET OUT  
THERE AND ENJOY IT! THE QUIET CONDITIONS WILL COME TO AN END TONIGHT  
AS WARM AIR ADVECTION (WAA) STRENGTHENS ALOFT. WITH ENOUGH  
SATURATION IN PLACE, WEAK INSTABILITY WILL BE PRESENT VIA TALL  
SKINNY CAPE PROFILES WITH MAGNITUDES OF ABOUT 500 J/KG. THIS WILL  
PROMOTE SCATTERED SHOWERS MAINLY ALONG AND EAST OF THE JAMES RIVER  
AFTER MIDNIGHT. NO SEVERE STORMS ARE EXPECTED BUT SOME OF THESE  
SHOWERS COULD BE CAPABLE OF A FEW RUMBLES OF THUNDER OR STRAY  
LIGHTNING STRIKE. THESE SHOWERS WILL PERSIST THROUGH THE REST OF THE  
OVERNIGHT HOURS BEFORE WANING TOMORROW MORNING. LOW TEMPERATURES  
WILL FALL TO THE 50S.  
 
REMNANT CLOUD COVER AND WEAKENING SHOWERS ARE EXPECTED TOMORROW  
MORNING. SHOULD SEE A DECENT BREAK IN CLOUD COVER FOR THE AFTERNOON  
HOURS THOUGH. THIS WILL ALLOW FOR HIGH TEMPERATURES TO WARM TO THE  
70S AND 80S ACROSS THE AREA. A WEAK BOUNDARY WILL BE SLOWLY SLIDING  
INTO THE AREA DURING THE AFTERNOON HOURS. WHERE THIS BOUNDARY SETS  
UP IS A BIT UNCERTAIN AT THIS TIME BUT IT IS LOOKING TO LIE ALONG  
AND SOUTH OF HIGHWAY-14. THIS BOUNDARY LOOKS TO SPARK ANOTHER ROUND  
OF CONVECTION DURING THE AFTERNOON HOURS. WITH CAPE VALUES UP TO  
AROUND 1,000 J/KG AND SOME VERTICAL SHEAR, A COUPLE OF STRONGER  
STORMS ARE POSSIBLE WITH GUSTY WINDS AND SMALL HAIL. THAT SAID,  
DESPITE AN ENTRANCE REGION OF AN UPPER LEVEL JET RESIDING OVER THE  
FORECAST AREA, SUFFICIENT VERTICAL SHEAR WILL NOT BE PRESENT UNTIL  
ABOVE 7 KM. THIS LOOKS TO ALLOW FOR SOME TILTING OF UPDRAFTS BUT  
THINK THAT IT WILL NOT BE SUFFICIENT ENOUGH FOR STORMS TO BECOME  
SEVERE. ON TOP OF THE MARGINAL SHEAR, A SHORTWAVE TROUGH WILL BE  
PASSING THROUGH THE AREA THROUGHOUT THE DAY. THE TIMING OF THIS WAVE  
LOOKS TO BE A BIT OFF AS WELL SINCE THIS WAVE MAY BE A BIT TOO FAST  
AND EXIT THE AREA BY THE LATE AFTERNOON OR EARLY EVENING HOURS. THAT  
SAID, HAVE INCLUDED CHANCE POPS (30-50%) FOR THE SHOWERS AND STORMS.  
ANY CHANCE FOR RAIN WILL COME TO AN END DURING THE EVENING HOURS.  
LOWS WILL FALL TO THE 50S OVERNIGHT.  
 
THURSDAY WILL BE A DRY DAY ACROSS THE NORTHERN PLAINS AS SHORTWAVE  
RIDGING WILL PUSH INTO THE AREA ALOFT. HIGHS WILL REMAIN IN THE 70S  
AND 80S WITH LOWS FALLING TO THE 50S. FRIDAY LOOKS TO BEGIN DRY BUT  
LATEST TRENDS HAVE RAIN BEGINNING FRIDAY AFTERNOON ACROSS PORTIONS  
OF CENTRAL AND SOUTH CENTRAL SOUTH DAKOTA AS A MID LEVEL WAVE BEGINS  
TO ENCROACH ON THIS AREA. WITH CLOUDS AND RAIN POSSIBLE DURING THE  
DAYLIGHT HOURS, HIGHS WILL REMAIN IN THE 70S TO LOW 80S THOUGH BE A  
BIT COOLER THAN THURSDAY'S HIGHS.  
 
RAIN CHANCES WILL INCREASE FRIDAY NIGHT, NOW UP TO A 20-40% CHANCE  
AND EVEN FURTHER ON SATURDAY AS THE PREVIOUSLY MENTIONED MID AND  
UPPER LEVEL WAVE PUSHES FURTHER EAST INTO THE FORECAST AREA. CHANCES  
FOR RAIN WILL INCREASE UP TO A 30-60% CHANCE. RAIN AND ABUNDANT  
CLOUD COVER WILL KEEP HIGH TEMPERATURES COOLER, DOWN TO THE 70S  
THROUGHOUT THE DAY. THE LOW WILL BE PUSHING EASTWARDS ON SUNDAY  
WHICH WILL RESULT IN DECREASING CHANCES FOR RAIN THROUGHOUT THE DAY.  
SUNDAY WILL AGAIN BE A COOLER DAY WITH HIGHS REMAINING IN THE 70S.  
LITTLE IF ANY INSTABILITY WILL BE PRESENT SO WHILE A FEW RUMBLES OF  
THUNDER ARE POSSIBLE, PLAIN RAIN LOOKS TO BE ON THE TABLE FOR THE  
WEEKEND. LATEST NBM 48 HOUR PRECIPITATION PROBABILITIES SHOW A 30-  
50% CHANCE FOR RAINFALL TOTALS TO EXCEED A QUARTER OF AN INCH OVER  
THE WEEKEND, HIGHEST TOWARDS CENTRAL AND SOUTH CENTRAL SOUTH DAKOTA.  
ALL THIS TO SAY THAT THIS HOLIDAY WEEKEND IS LOOKING TO BE A  
RAINY/DREARY WEEKEND. WHILE THIS IS WHAT THE GENERAL CONSENSUS OF  
LATEST INFORMATION POINTS TO, DETAILS CAN STILL CHANGE HEADING INTO  
THE HOLIDAY WEEKEND. PLEASE CONTINUE TO MONITOR THE LATEST FORECAST  
FOR THE MOST UP TO DATE INFORMATION.  
 

 
   
AVIATION /06Z TAFS THROUGH 06Z THURSDAY/
 
 
ISSUED AT 1044 PM CDT TUE AUG 26 2025  
 
VFR CONDITIONS EXPECTED THROUGH THE PERIOD. SCATTERED SHOWERS ARE  
SET TO DEVELOP THIS MORNING MAINLY EAST OF THE JAMES RIVER. THE  
BETTER CHANCES OF SHOWERS WILL BE EAST OF I-29 INTO SOUTHWEST  
MINNESOTA AND NORTHWEST IOWA, BUT STILL ENOUGH CONFIDENCE FOR A  
TEMPO GROUP AT KFSD AND A PROB30 AT KSUX DUE TO VFR SHOWERS. SHOWERS  
PUSH EAST OF THE AREA LATE THIS MORNING, BUT ADDITIONAL SHOWERS AND  
EVEN SOME THUNDERSTORMS ARE EXPECTED TO DEVELOP IN THE AFTERNOON AND  
EVENING AS A BOUNDARY MOVES INTO THE AREA. WITH THIS ACTIVITY  
EXPECTED TO BE VERY SCATTERED NATURE, NOT ENOUGH CONFIDENCE TO  
INCLUDE MENTION IN THE TAFS AT THIS TIME. CAN AT LEAST SAY THESE  
AFTERNOON SHOWERS/STORMS ARE FAVORING TO DEVELOP IN AREAS SOUTH OF  
HIGHWAY-14.  
 
WINDS WILL BE OUT OF THE SOUTHEAST THIS MORNING AROUND 5-10 KTS,  
TURNING TO THE NORTHEAST NORTH OF I-90 IN THE AFTERNOON DUE TO THE  
AFOREMENTIONED BOUNDARY. JUST AHEAD OF THE BOUNDARY AT KFSD AND  
KSUX, WINDS WILL TURN TO THE SOUTHWEST THIS AFTERNOON AND EVENING.  
WINDS LOOK TO GRADUALLY DIMINISH THROUGH THE EVENING INTO THE  
OVERNIGHT.  
 

 
   
FSD WATCHES/WARNINGS/ADVISORIES
 
 
SD...NONE.  
MN...NONE.  
IA...NONE.  
NE...NONE.  
 

 
 

 
 
DISCUSSION...MEYERS  
AVIATION...SAMET  
 
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