272  
FXUS63 KABR 121716 AAC  
AFDABR  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE ABERDEEN SD  
1216 PM CDT SAT SEP 12 2026  
   
KEY MESSAGES
 
 
- COOLER TEMPERATURES TAKE HOLD THIS WEEKEND, WITH HIGHS IN THE  
60S TO LOW 70S EXPECTED. THIS TREND WILL CONTINUE THROUGH THE  
START OF NEXT WEEK, WITH THE POSSIBLE EXCEPTION OF A BRIEF  
WARMUP TO NEAR-NORMAL ON MONDAY.  
 
- ADDITIONAL CHANCES FOR RAIN SHOWERS TO PERHAPS WEAK  
THUNDERSTORMS COME SUNDAY AND MONDAY MORNINGS. OVER BOTH DAYS,  
MUCH OF THE FORECAST AREA WILL SEE BETWEEN HALF-AN-INCH TO AN  
INCH OF RAINFALL IN TOTAL.  
 

 
   
UPDATE
 
 
ISSUED AT 1207 PM CDT SAT SEP 12 2026  
 
UPDATED DISCUSSION FOR THE 18Z TAFS BELOW.  
 
UPDATE ISSUED AT 1011 AM CDT SAT SEP 12 2026  
 
SATELLITE INDICATES INCREASING CLOUDS MOVING IN WEST OF THE MO  
RIVER OUT OF WY/MT PER MID LEVEL MOISTURE AND SHORTWAVE ENERGY.  
THESE CLOUDS WILL CONTINUE TO SPREAD EASTWARD OVER THE REGION.  
THERE ARE STILL SOME LIGHT RETURNS ON RADAR OVER NORTHWESTERN  
AND PORTIONS OF NORTH CENTRAL SD, HOWEVER, WITH THE SURFACE HIGH  
DOMINANT, MUCH IF ANY OF THIS IS NOT HITTING THE GROUND AND IF  
SO, WILL ONLY BE LIGHT SPRINKLES FOR THE NEXT FEW HOURS. HIGH  
PRESSURE WILL REMAIN DOMINANT OVER THE AREA FOR THE REST OF THE  
DAY AND THIS EVENING WITH DRY WEATHER EXPECTED. TEMPS ARE  
CURRENTLY IN THE UPPER 50S TO THE LOWER 60S AND DEWPOINTS IN THE  
40S. FORECAST REMAINS ON TRACK WITH MORE CHANCES OF LIGHT RAIN  
OVERNIGHT OVER PORTIONS OF THE CWA.  
 
UPDATE ISSUED AT 629 AM CDT SAT SEP 12 2026  
 
SEE BELOW FOR AN AVIATION FORECAST DISCUSSION FOR THE 12Z TAFS.  
 

 
   
DISCUSSION
 
 
ISSUED AT 220 AM CDT SAT SEP 12 2026  
 
THERE ARE A FEW LIGHT SHOWERS LINGERING OVER PARTS OF CENTRAL SOUTH  
DAKOTA EARLY THIS MORNING (AS OF ~06Z). EXPECTATIONS OVER THE NEXT  
FEW HOURS ARE THAT SHOWERS WILL CONTINUE TO MOVE INTO THE AREA, BUT  
WILL DISSIPATE SHORTLY AFTER MOVING IN. BY THIS AFTERNOON, EXPECT  
SKIES TO BE CLEAR OF RAIN SHOWERS, ALTHOUGH CLOUDY SKIES MAY PERSIST  
TODAY.  
 
CHANCES FOR RAIN WILL RETURN ON SUNDAY. A JET STREAK WILL DEVELOP IN  
THE RIGHT ENTRANCE REGION OF THE DEPARTING UPPER-LEVEL TROUGH TO THE  
EAST, PROVIDING THE DIVERGENCE ALOFT THAT WILL HELP WITH DEVELOPMENT  
OF SHOWERS AND STORMS. CAMS HIGHLIGHT TWO MAIN AREAS FOR STORM  
DEVELOPMENT EARLY SUNDAY MORNING, ONE OVER NORTH CENTRAL AND  
NORTHEASTERN SOUTH DAKOTA AND THE OTHER OVER CENTRAL TO SOUTH  
CENTRAL SOUTH DAKOTA. THE LATTER AREA SHOWS A BIT MORE ORGANIZATION  
AND BETTER CHANCES FOR STORMS, BUT SEVERE POTENTIAL HAS WANED IN  
THAT AREA. EVEN HEAVY RAIN IS LOOKING LESS LIKELY, DOWN TO ABOUT A  
10-30% CHANCE TO SEE A QUARTER OF AN INCH THROUGH SUNDAY MORNING.  
 
AN UPPER-LEVEL TROUGH TO THE WEST WILL HELP TO DEVELOP ANOTHER LOW  
PRESSURE CENTER AND ASSOCIATED FRONTAL BOUNDARY SET TO TRACK ACROSS  
THE REGION MONDAY. ALONG AND AHEAD OF THIS FRONT ADDITIONAL CHANCES  
FOR RAIN ARE EXPECTED EARLY MONDAY MORNING. LATEST NBM PROBABILITIES  
SHOW A BIT OF AN INCREASE FROM 24 HOURS AGO IN THE PROBABILITY TO  
RECEIVE HALF AN INCH OF RAIN. THROUGH MONDAY EVENING, CHANCES NOW  
SIT AT ABOUT 60-80% OF HALF AN INCH (AND 20-45% FOR ONE INCH) OVER  
MOST OF THE FORECAST AREA. EXPECTATIONS FOR THE HIGHEST TOTALS ARE  
ALONG THE NORTH DAKOTA/SOUTH DAKOTA BORDER. EURO AND CANADIAN  
ENSEMBLES ARE FAIRLY IN LINE WITH THESE SAME PROBABILITIES, BUT  
INTERESTINGLY THE GEFS SHOWS LESS THAN A 5% CHANCE FOR HALF AN INCH  
OF RAIN ACROSS THE BOARD. PERHAPS THE POSSIBLE EXPLANATION FOR THIS  
SEEMINGLY EXTREME SCENARIO IS THAT THE COLDER NEAR-SURFACE  
ENVIRONMENT MAY LIMIT DEEPER CONVECTION WITH THIS SYSTEM. HOWEVER  
WITH NEARLY 40 KNOTS OF SPEED SHEAR ABOVE THE WARM LAYER AND THE  
PRESENCE OF THE FRONT, SHOWERS TO WEAK THUNDERSTORMS WILL LIKELY  
STILL BE ABLE TO FORM. AT THIS POINT CONDITIONS DO NOT APPEAR  
FAVORABLE FOR SEVERE WEATHER FROM THESE STORMS.  
 
AFTER THE PASSAGE OF YESTERDAY'S FRONT, TEMPERATURES WILL TAKE A  
DROP INTO THE 60S TO LOW 70S OVER THE WEEKEND, ABOUT 5-10 DEGREES  
BELOW NORMAL FOR MID-SEPTEMBER. THIS TREND WILL CONTINUE INTO THE  
START OF NEXT WEEK, WITH THE EXCEPTION OF A BRIEF WARMUP TO NEAR-  
NORMAL FOR CENTRAL AND NORTH CENTRAL SOUTH DAKOTA ON MONDAY. LONGER  
RANGE MODELS SHOW SINGS OF A WARMUP BY THE END OF NEXT WEEK TO AT  
LEAST NEAR-NORMAL TEMPERATURES ACROSS THE FORECAST AREA.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
 
 
ISSUED AT 1207 PM CDT SAT SEP 12 2026  
 
TERMINALS KABR,KATY,KPIR,KMBG  
 
MID TO HIGH BASED CLOUDS CONTINUE TO TRACK EASTWARD WITH INCREASED  
CLOUD COVER OVER THE REGION THIS EVENING THROUGH TONIGHT AS A  
SHORTWAVE TRACKS ACROSS THE AREA. VFR CIGS ARE OVERALL FORECAST  
THROUGH THE END OF THE TAF PERIOD. WITH THIS SHORTWAVE, THERE IS  
AN ISOLATED THREAT OF SPOTTY TO BANDS OF LIGHT RAIN (AND PERHAPS  
WEAK THUNDERSTORMS) EARLY SUNDAY MORNING POSSIBLY AFFECTING  
KPIR AND KABR AT THIS TIME AND AFFECTING KATY AFTER 10Z. LITTLE  
IF ANY QPF IS EXPECTED PER DRY LOW LEVELS AS A HIGH PRESSURE  
REMAINS DOMINANT. WINDS WILL CONTINUE OUT OF THE NORTH AND  
NORTHWEST AND SWITCHING TO EAST/NORTHEAST FOR SUNDAY. WILL MAKE  
ADJUSTMENTS TO TAFS AS NEEDED.  
 

 
   
ABR WATCHES/WARNINGS/ADVISORIES
 
 
SD...NONE.  
MN...NONE.  
 

 
 

 
 
UPDATE...MMM  
DISCUSSION...BC  
AVIATION...MMM  
 
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