912  
FXUS63 KABR 040639  
AFDABR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE ABERDEEN SD  
139 AM CDT FRI SEP 4 2026  
   
KEY MESSAGES  
 
- AREAS OF FOG ARE EXPECTED THIS MORNING OVER NORTHEAST SD INTO WEST  
CENTRAL MN WITH REDUCTIONS IN VISIBILITY POTENTIALLY DOWN TO 2 MILES  
OR LESS.  
 
- THERE IS A MARGINAL RISK (LEVEL 1 OUT OF 5) FOR SEVERE STORMS OVER  
CENTRAL AND NORTHEASTERN SD AND WEST CENTRAL MN SATURDAY EVENING  
INTO THE OVERNIGHT HOURS. THE PRIMARY HAZARDS WILL BE 1 INCH IN  
DIAMETER HAIL AND 60 MPH WIND GUSTS.  
 
- OUR WARMING TREND CONTINUES INTO THE WEEKEND, PEAKING AT 15 TO 20  
DEGREES ABOVE NORMAL SATURDAY. HIGHS IN THE UPPER 80S TO UPPER 90S  
ARE EXPECTED.  
 
 
   
DISCUSSION  
 
ISSUED AT 139 AM CDT FRI SEP 4 2026  
 
CENTRAL AND NORTHEASTERN SD AND WEST CENTRAL MN WILL BE GETTING A  
LITTLE BIT OF A BREAK FROM THE SCATTERED EARLY MORNING SHOWERS AND  
STORMS TODAY. WHILE THERE WILL NOT BE ANY SHOWERS, WEAKER WINDS OVER  
NORTHEASTERN SD AND WEST CENTRAL MN AS WELL AS HIGH RELATIVE  
HUMIDITY VALUES WILL HELP PATCHY TO AREAS OF FOG TO DEVELOP THIS  
MORNING. THIS FOG COULD CAUSE LOCALIZED AREAS OF VISIBILITIES TO  
DROP BELOW 2 MILES AT TIMES THIS MORNING OVER PORTIONS OF  
NORTHEASTERN SD AND WEST CENTRAL MN, WHICH SHOULD DISSIPATE ONCE THE  
SUN RISES. AS THIS IS HAPPEN, AN UPPER LEVEL RIDGE WILL START TO  
BUILD OVER SD INTO THE WEEKEND. THE FLOW UNDER THIS RIDGE WILL HELP  
WARM, MOIST AIR TO MOVE INTO CENTRAL AND NORTHEASTERN SD TODAY AND  
INTO THE WEEKEND. TEMPERATURES TODAY WILL BE ABOUT 10-15 DEGREES  
WARMER THAN NORMAL, WITH HIGHS IN THE UPPER 80S TO MID 90S. THINGS  
WILL WARM EVEN MORE SATURDAY, WITH HIGHS IN THE UPPER 80S TO UPPER  
90S. WITH THE WARM, HUMID AIR AROUND SATURDAY, THE HEAT INDEX VALUES  
COULD REACH THE TRIPLE DIGITS IN SOME AREAS OVER CENTRAL SD.  
 
MODELS ARE FORECASTING MULTIPLE UPPER-LEVEL SHORTWAVES TO MOVE ALONG  
THE TOP OF THE RIDGE OVER SD. THERE IS SLIGHTLY LOWER CONFIDENCE IN  
THE TIMING OF THESE SHORTWAVES AS THE MODELS ARE NOT IN CONSENSUS ON  
IT. WHILE THESE SHORTWAVES COULD PROVIDE UPPER-LEVEL SUPPORT FOR  
SHOWER AND STORM DEVELOPMENT, THERE ALSO NEEDS TO BE A SOURCE OF  
LIFT AT THE SURFACE. THERE WILL BE A LEE OF THE ROCKIES SURFACE  
TROUGH SITTING OVER WESTERN SD AND MODELS ARE HINTING AT AN ATTACHED  
WARM FRONT SLOWLY MOVING IN AND SITTING OVER THE AREA THIS AFTERNOON  
AND INTO THE WEEKEND. THESE BOUNDARIES WILL BE ABLE TO PROVIDE SOME  
OF THE LIFT NEEDED FOR SHOWER AND STORM DEVELOPMENT, THOUGH THE  
STORMS WILL NEED TO OVERCOME A FAIRLY DECENT CAP TO HAVE ANY  
LONGEVITY AND/OR BECOME SEVERE. THIS CAP IS FROM AN INVERSION DUE TO  
THE WARM AIR MOVING IN ALOFT. INSTABILITY WILL BE BUILDING OVER  
CENTRAL AND NORTHEASTERN SD TODAY, WITH CAPE VALUES OF 1000-2000  
J/KG OVER THE AREA THIS EVENING. WITH THIS INSTABILITY, AS WELL AS  
THE MOISTURE MOVING IN AND THE LIFT FROM THE SURFACE TROUGH AND WARM  
FRONT, SHOWERS AND STORMS COULD TRY TO DEVELOP LATE THIS AFTERNOON  
INTO TONIGHT. HOWEVER, THERE IS LOWER CONFIDENCE IN THIS AS THEY  
WOULD HAVE TO BE ABLE TO OVERCOME THE CAP. AS STUFF TRIES TO  
DEVELOP, IT COULD CAUSE SOME ISOLATED PULSE, POP UP SHOWERS AND  
STORMS THAT COULD TRY TO GET GOING BUT ARE NOT ABLE TO STAY UP FOR  
VERY LONG. IF ANYTHING WERE ABLE TO OVERCOME THE CAP AND BECOME A  
STRONGER STORM, THERE WILL BE LAPSE RATES OF 7-8 C/KM AND BULK SHEAR  
VALUES OF 35-40 KTS THAT COULD HELP THE STORM TO HAVE SOME LARGER  
HAIL DEVELOP, THOUGH THERE IS VERY LOW CONFIDENCE THAT THIS WILL  
HAPPEN.  
 
DEPENDING ON WHEN THE UPPER-LEVEL SHORTWAVE MOVE THROUGH, THESE PULSY  
SHOWERS AND STORMS COULD POP UP AND MOVE OVER CENTRAL AND  
NORTHEASTERN SD TONIGHT THROUGH SUNDAY. THE MODEL SOUNDINGS SHOW  
THAT THERE IS PLENTY OF INSTABILITY AND MOISTURE THAT STICKS AROUND  
THOUGH SUNDAY TO HELP THINGS DEVELOP. THE INSTABILITY WILL INCREASE  
SATURDAY AFTERNOON AND THROUGH THE NIGHT TO BE BETWEEN 1000-3000  
J/KG OVER SD. WITH STEEP MID-LEVEL LAPSE RATES BETWEEN 6-8 C/KM AND  
BULK SHEAR VALUES OF 30-35 KTS OVER CENTRAL AND NORTHEASTERN SD, THE  
ENVIRONMENT WILL BE PRIMED FOR SEVERE STORMS TO DEVELOP WITH LARGE  
HAIL AND GUSTY WINDS SATURDAY AFTERNOON AND INTO THE OVERNIGHT  
HOURS. THERE IS A MARGINAL RISK (LEVEL 1 OF 5) FOR THESE STORMS TO  
BECOME SEVERE. WHILE THESE STORMS WILL MOST LIKELY DEVELOP ALONG THE  
SURFACE TROUGH IN WESTERN SD AND THEN MOVE INTO CENTRAL SD, THERE IS  
LOWER CONFIDENCE IN THE TIMING AND HOW FAR EAST THEY WILL MAKE IT DO  
TO MODELS ALL VARYING THE OUTCOMES BECAUSE OF HOW THEY HANDLE THE  
UPPER-LEVEL SUPPORT FROM THE SHORTWAVES. THIS WILL NEED TO HAVE AN  
EYE KEPT ON IT TO SEE IF MODELS START TO COME TO MORE OF A  
CONSENSUS.  
 
 
   
AVIATION /06Z TAFS THROUGH 06Z SATURDAY/  
 
ISSUED AT 1228 AM CDT FRI SEP 4 2026  
 
TERMINALS KABR,KATY,KPIR,KMBG  
 
VFR CONDITIONS ARE FORECAST TO START OFF THE TAF PERIOD.  
ALTHOUGH, WILL BE WATCHING POTENTIAL FOR FG/BR AND IFR CIGS  
ACROSS NORTHERN SD CLOSER TO 12Z THIS MORNING. FOR NOW HAVE ONLY  
INCLUDED A TEMPO GROUP FOR THIS AT KABR WHERE MODELS ARE SHOWING  
A BETTER LIKELIHOOD. NOT OUT OF THE QUESTION FOR KMBG/KATY TO  
GET INTO SOME OF THIS, BUT WITH LESS CONFIDENCE WILL OPT TO  
LEAVE OUT OF 06Z TAFS FOR NOW AND CONTINUE TO MONITOR TRENDS  
THROUGH THE EARLY MORNING AND AMEND IF NEEDED.  
 
 
   
ABR WATCHES/WARNINGS/ADVISORIES  
 
SD...NONE.  
MN...NONE.  
 
 
 
 
 
DISCUSSION...12  
AVIATION...TMT  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SD Page
The Nexlab MN Page
Main Text Page