125  
FXUS63 KABR 121830  
AFDABR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE ABERDEEN SD  
130 PM CDT WED AUG 12 2026  
   
KEY MESSAGES  
 
- THERE IS A SLIGHT (LEVEL 2 OF 5) TO MARGINAL (LEVEL 1 OF 5) RISK  
FOR SEVERE STORMS TO DEVELOP THIS AFTERNOON WEST RIVER, MIGRATING  
EAST THROUGH THE EVENING AND OVERNIGHT. MAIN THREATS INCLUDE WIND  
GUSTS OF 60 TO 70 MPH AND HAIL UP TO 1 INCH IN DIAMETER.  
ADDITIONALLY, HEAVY RAINFALL COULD LEAD TO LOCALIZED FLOODING IN A  
FEW AREAS.  
 
-SOME WILDFIRE SMOKE HAS THE ABILITY TO MAKE IT TO THE SURFACE THIS  
EVENING OVER PORTIONS OF NORTHEASTERN SD. THIS SMOKE COULD REDUCE  
AIR QUALITY SLIGHTLY AND CAUSE SOME ISSUES TO THOSE WHO ARE  
SENSITIVE.  
 
-NEXT CHANCE FOR SHOWERS AND STORMS WILL BE THURSDAY NIGHT INTO  
FRIDAY MORNING OVER CENTRAL AND NORTHEASTERN SD. THESE STORMS ARE  
FORECAST TO STAY BELOW SEVERE CRITERIA.  
 
 
   
DISCUSSION  
 
ISSUED AT 130 PM CDT WED AUG 12 2026  
 
WILDFIRE SMOKE WILL CONTINUE TO MOVE IN TODAY. WHILE MOST OF THIS  
SMOKE WILL STAY ABOVE THE SURFACE, PORTIONS OF NORTHEASTERN SD COULD  
SEE SOME OF THIS SMOKE GET TO THE SURFACE. THE CONCENTRATION OF  
SMOKE WILL NOT BE ENOUGH TO CAUSE A DECREASE IN VISIBILITIES, THOUGH  
THE AIR QUALITY WILL DROP INTO THE MODERATE AIR QUALITY INDEX  
CATEGORY. THOSE WHO ARE SENSITIVE TO AIR POLLUTANTS COULD BE  
IMPACTED SLIGHTLY. TEMPERATURES TODAY ARE ON TRACK TO BE AROUND  
NORMAL, WITH HIGHS IN THE 80S.  
 
AS A WEAK UPPER-LEVEL SHORTWAVE MOVES OVER SD THIS AFTERNOON INTO  
THE EVENING, A SURFACE BOUNDARY WILL BE MOVING INTO CENTRAL AND  
NORTHEASTERN SD. THIS SHORTWAVE AND SURFACE BOUNDARY WILL HELP TO  
PROVIDE SOME FORCING FOR SHOWER AND STORM DEVELOPMENT TODAY AS THEY  
MOVE OVER AN AREA WITH SOME INSTABILITY. THE MODELS ARE SHOWING CAPE  
VALUES OF 1000-2000 J/KG OVER CENTRAL AND PORTIONS OF NORTHEAST SD  
THIS AFTERNOON INTO THE EVENING, DECREASING AS THE SURFACE BOUNDARY  
MOVES IN. MID-LEVEL FLOW FROM THE INTERMOUNTAIN WEST WILL HELP TO  
MOVE IN MOISTURE IN THE MID-LEVELS AND CREATE A BIT OF AN INVERTED-V  
SOUNDING. THE INVERTED-V SOUNDING INDICATES 2 THINGS: THAT THE  
CONVECTION WILL LIKELY BE ELEVATED, AND THAT STRONG WINDS FROM  
MICROBURSTS WILL BE POSSIBLE IN THE STORMS. THERE IS A SLIGHT (LEVEL  
2 OF 5) TO MARGINAL (LEVEL 1 OF 5) RISK THAT ANY STORMS THAT  
DEVELOPS COULD BECOME SEVERE, WITH THE HIGHEST RISK FOR SEVERE  
STORMS OVER SOUTH CENTRAL SD. THE MAIN HAZARD WILL BE STRONG WIND  
GUSTS OF 60-70 MPH. EVEN THOUGH THERE WILL BE WEAKER LAPSE RATES, IF  
ANY ISOLATED CELL DOES DEVELOP IN FRONT OF THE BOUNDARY, THERE IS A  
RISK FOR HAIL UP AROUND 1 INCH. ADDITIONALLY, WITH THE MOISTURE  
MOVING IN FROM THE INTERMOUNTAIN WEST HELPING TO FEED THE STORMS,  
THERE COULD BE HEAVY RAINFALL AT TIMES. IF MULTIPLE CELLS WERE TO  
MOVE OVER THE SAME AREA, THAT RAINFALL COULD ADD UP AND CREATE  
LOCALIZED FLOODING AT TIMES. THESE STORMS SHOULD MOVE OUT OF CENTRAL  
AND NORTHEASTERN SD DURING THE EARLY OVERNIGHT HOURS, WITH THE  
POTENTIAL FOR A FEW LINGERING SHOWERS INTO EARLY THURSDAY MORNING.  
 
BEHIND THE SURFACE BOUNDARY, COOLER AIR WILL BE MOVING IN THURSDAY.  
THIS WILL CAUSE TEMPERATURES TO FALL SLIGHTLY, TO BE ABOUT 5 TO 10  
DEGREES BELOW NORMAL THROUGH THE WEEKEND. HIGH TEMPERATURES WILL BE  
IN THE 70S DURING THIS TIME. THERE IS A LITTLE BIT OF VARIABILITY IN  
THE MODELS AS TO PRECIPITATION CHANCES THURSDAY. SOME MODELS KEEP  
SOME ISOLATED SHOWERS AND STORMS OVER CENTRAL AND NORTHEASTERN SD  
THURSDAY MORNING AND AFTERNOON, WHILE OTHER MODELS KEEP THE SHOWERS  
AND STORMS OUT OF THE AREA. THE NEXT LARGER CHANCE FOR SHOWERS AND  
STORMS TO MOVE IN WILL BE THURSDAY NIGHT INTO FRIDAY AS THE LEE OF  
THE ROCKIES SURFACE TROUGH STARTS TO MOVE OVER AND THROUGH SD.  
MODELS SHOW VERY WEAK INSTABILITY OVER NORTHEASTERN AND CENTRAL SD  
AS WELL AS WEAK LAPSE RATES AND SHEAR. BECAUSE OF THIS, THESE  
SHOWERS AND STORMS WILL LIKELY STAY AS WEAK STORMS WITH LITTLE  
CHANCE TO BECOME SEVERE.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z THURSDAY/  
 
ISSUED AT 1232 PM CDT WED AUG 12 2026  
 
TERMINALS KABR,KATY,KPIR,KMBG  
 
MAINLY VFR/MVFR CONDITIONS WILL BE AROUND THIS AFTERNOON AND  
EVENING, EXCEPT FOR SOME IFR AT KPIR DUE TO LOW CLOUDS FOR ANOTHER  
HOUR OR SO, BEFORE SOME SHOWERS AND STORMS START TO MOVE IN OVER THE  
TERMINALS. THE STORMS HAVE A MARGINAL RISK (LEVEL 1 OF 5) TO BECOME  
SEVERE IF THEY DEVELOP, WITH OCCASIONAL STRONG WIND GUSTS OF 60-70  
MPH POSSIBLE. THESE SHOWERS AND STORMS WILL BE MOVING OUT DURING THE  
EVENING AND EARLY OVERNIGHT HOURS. KATY COULD SEE SOME WILDFIRE  
SMOKE REACHING THE SURFACE THIS EVENING, THOUGH THIS SMOKE SHOULD  
NOT AFFECT VISIBILITY AND CEILINGS.  
 
 
   
ABR WATCHES/WARNINGS/ADVISORIES  
 
SD...NONE.  
MN...NONE.  
 
 
 
 
 
DISCUSSION...12  
AVIATION...12  
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