271  
FXUS63 KABR 290527 AAC  
AFDABR  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE ABERDEEN SD  
1227 AM CDT WED APR 29 2026  
   
KEY MESSAGES  
 
- CHANCES FOR LIGHT RAIN ARE POSSIBLE OVER THE NEXT FEW DAYS  
MAINLY OVER FAR SOUTH CENTRAL SOUTH DAKOTA THROUGH THIS  
EVENING (30-50%) AND MORE WIDELY SCATTERED (20-40%) FOR  
WEDNESDAY AND THURSDAY. THUNDERSTORMS ARE POSSIBLE WEDNESDAY  
AFTERNOON AND EVENING, NO SEVERE WEATHER IS ANTICIPATED.  
 
- HIGH TEMPERATURES 5 TO 15 DEGREES BELOW NORMAL EXPECTED  
THROUGH THE WORK WEEK. HIGHS WILL BE IN THE 50S THROUGH THAT  
PERIOD. WEEKEND HIGHS WILL INCREASE SLIGHTLY INTO THE 60S.  
 
 
   
UPDATE  
 
ISSUED AT 1217 AM CDT WED APR 29 2026  
 
SEE BELOW FOR AN AVIATION FORECAST DISCUSSION FOR THE 06Z TAFS.  
 
UPDATE ISSUED AT 816 PM CDT TUE APR 28 2026  
 
AN AREA OF SHOWERS CONTINUES TO MOVE SOUTHEAST ACROSS SOUTHWEST  
SD, AND IF IT HOLDS TOGETHER, ITS MOVEMENT MAY BRING IT ACROSS  
THE FAR SOUTHWEST CWA OVER THE NEXT FEW HOURS. HAVE THEREFORE  
EXPANDED POPS (20-40% CHANCES) ACROSS THE SOUTHWEST COUNTIES A  
BIT MORE IN AREAL COVERAGE. SKIES HAVE ALSO CLEARED NICELY  
ACROSS CENTRAL SD THIS EVENING, SO REDUCED SKY COVER THERE.  
 
 
   
DISCUSSION  
 
ISSUED AT 143 PM CDT TUE APR 28 2026  
 
A BROAD TROUGHING PATTERN CONTINUES OVER THE CENTRAL AND NORTHERN  
PLAINS, ON THE SOUTHERN SIDE OF A BROAD LOW SPINNING OVER CANADA.  
MODELS INDICATE A WEAK EMBEDDED SHORTWAVE, WITH ITS AXIS OVER WY,  
TRACKING EASTWARD AND OVER SD/NE THROUGH LATE THIS AFTERNOON AND  
EVENING, WITH THE CWA ON THE BACKSIDE OF IT BY EARLY WEDNESDAY  
MORNING. ANOTHER EMBEDDED AND STRONGER SHORTWAVE HAS BEEN THE MAIN  
FOCUS FOR RAIN SHOWERS FURTHER SOUTH IN NEBRASKA. SHORTWAVE PULSES  
ON THE PVA SIDE OF THIS NORTHERN WAVE IS PRODUCING THE BULK OF THE  
RAIN SHOWERS OVER SOUTHWESTERN SD WITH THE NORTHERN EDGE OF THIS  
RAIN CURRENTLY OVER SOUTH CENTRAL SD, MAINLY JONES AND LYMAN COUNTIES  
PER RADAR. THIS WILL BE THE MAIN FOCUS FOR ONGOING CHANCES OF RAIN  
WHERE WE HAVE BETTER BETTER 1000-500MB. NBM IS A LITTLE BIT MORE  
AGGRESSIVE ON THE NORTHERN EXTEND OF THIS RAIN (AND POP CHANCES) THAN  
CAMS, WHICH CONTINUE TO KEEP THE BULK OF IT SOUTH OF THE CWA THROUGH  
THIS EVENING.  
 
LATE THIS EVENING THROUGH EARLY WED MORNING, ANOTHER  
WEAK EMBEDDED SHORTWAVE OVER MT/WY WILL BRING MORE CHANCES OF LIGHT  
RAIN WITH CAMS INDICATING SPOTTY CONVECTIVE SHOWERS MOVING IN FROM  
WESTERN SD AND TRACKING SOUTHEAST. HOWEVER, CAMS SHOW THESE EITHER  
WEAKENING OR DISSIPATING AS THEY MOVE IN OVER THE WESTERN CWA.  
ADDITIONAL DEVELOPMENT OF SPOTTY SHOWERS (HRRR) ARE POSSIBLE OVER  
PORTIONS OF SOUTH CENTRAL AND EAST CENTRAL SD HOWEVER HI RES MODELS  
ARE NOT TOO THRILLED AND VERY SPOTTY AND NBM DOES NOT HAVE ANYTHING.  
THESE WILL BE MOISTURE STARVED SO MOST LIKELY SPRINKLES AT MOST OR  
VIRGA. RAN WITH ECAM BETWEEN 00-12Z WITH POPS UP TO 15% AT MOST. SO  
LOW CONFIDENCE ON IF THEY WILL EVEN FORM AND WHERE THEY WILL  
INITIATE IF THEY DO. HREF PROBABILITY OF 0.01" THROUGH 12Z WEDNESDAY  
IS 30 TO 50% OVER PORTIONS OF SOUTH CENTRAL SD WITH THE HIGHEST PROB  
OVER STANLEY AND JONES WITH MOST OF THIS QPF THROUGH THIS EVENING  
NBM RUNS 40-70% FOR THIS SAME AREA SO NBM RUNNING A BIT MORE HOT  
WITH POP CHANCES AND QPF. THE 10-25% CHANCE WILL BE PRETTY SPLOTCHY  
OVER THE REST OF THE CWA (WITH THE EXCEPTION OF FAR NORTHEASTERN  
SD/WESTERN MN) PER THESE CONVECTIVE SHOWER POSSIBILITIES.  
 
THIS BROAD TROUGH OVERHEAD FOR WEDNESDAY PLUS ADDITIONAL SHORTWAVE  
ENERGY/PULSES AND DAYTIME HEATING, CAMS INDICATE THE DEVELOPMENT OF  
VERY SPOTTY ELEVATED CONVECTIVE SHOWERS/THUNDERSTORMS TRACKING  
NORTHWEST TO SOUTHEAST BETWEEN 18-03Z ACROSS THE CWA AS HREF  
COMPOSITE REFLECTING>40 DBZ PAINTBALLS AS WELL. INSTABILITY WILL BE  
WEAK WITH MUCAPE OF 500J/KG OR LESS AND MID LEVEL LAPSE RATES LESS  
THEN 7C. HOWEVER BULK SHEAR WILL BE AROUND 30KTS OUT OF THE  
NORTHWEST. SO THUNDERSTORMS COULD BE POSSIBLE WITH NO SEVERE WEATHER  
ANTICIPATED. ANY STRONGER RAIN SHOWER OR THUNDERSTORM COULD PRODUCE  
SUB SEVERE WINDS GIVEN AN INVERTED V SOUNDING. ANOTHER EMBEDDED  
POSITIVE TILTED SHORTWAVE MOVING IN OUT OF CANADA AND TRACKING OVER  
THE CWA WILL BRING ISOLATED SPOTTY CONVECTIVE SHOWERS ONCE AGAIN  
THURSDAY. HOWEVER FORCING AND INSTABILITY IS REALLY NOT THERE, SO IF  
SHOWERS DO FORM THEY WILL BE WEAK WITH POPS OF 15-20%.  
 
FINALLY, FOR THE END OF THE WEEK AS THIS UPPER LOW/TROUGH PUSHES  
MORE EASTWARD AND OVER THE EASTERN CONUS, MODELS INDICATE SPLIT FLOW  
OVER THE WESTERN CONUS WITH A RIDGE OVER THE PACIFIC NORTHWEST AND  
TROUGH OVER SOUTHERN CA/MEXICO. THE NORTHERN PLAINS WILL CONTINUE IN  
OVERALL NORTHWESTERLY FLOW ALOFT BETWEEN THE RIDGE TO OUR WEST AND  
TROUGH TO OUR EAST. THIS SHOULD OVERALL PRODUCE DRY WEATHER FRIDAY  
AND SATURDAY WITH MORE SHORTWAVES MOVING ACROSS THE REGION EARLY  
NEXT BRINGING SLIGHT CHANCES OF POPS (15-20%).  
 
WITH THIS OVERALL BROAD TROUGHING PATTERN, 850MB TEMPS CONTINUE TO  
BE BELOW AVERAGE THROUGH THE END OF THE WEEK, HOVERING A BIT ABOVE  
OR BELOW 0C, WITH VALUES AS LOW AS THE 10-20TH PERCENTILE. HIGHS FOR  
WEDNESDAY THROUGH FRIDAY WILL RANGE OVERALL IN THE 50S WITH TEMPS  
WARMING INTO THE 60S FOR THE WEEKEND. CLIMATE PREDICATION CENTER 6-  
10 DAY OUTLOOK (5/3-5/7) INDICATES BELOW AVERAGE IN PRECIP AND TEMP.  
 
 
   
AVIATION /06Z TAFS THROUGH 06Z THURSDAY/  
 
ISSUED AT 1217 AM CDT WED APR 29 2026  
 
TERMINALS KABR,KATY,KPIR,KMBG  
 
VFR CONDITIONS ARE FORECAST TO PREVAIL THROUGH THE TAF PERIOD.  
ISOLATED TO WIDELY SCATTERED -SHRA ARE FORECAST ACROSS THE  
REGION (MAINLY CENTRAL AND NORTH CENTRAL SOUTH DAKOTA) FROM  
ROUGHLY MID-DAY TODAY THROUGH LATE THIS EVENING, SO PROB30S HAVE  
BEEN INTRODUCED TO THE KPIR AND KMBG TAFS. PERHAPS A FEW BRIEF  
DROPS TO MVFR VSBY IN THE HEAVIER DOWNPOURS, BUT OVERALL  
THINKING VFR VSBYS, EVEN IN SHOWER ACTIVITY, SHOULD SUFFICE  
LATER TODAY.  
 
 
   
ABR WATCHES/WARNINGS/ADVISORIES  
 
SD...NONE.  
MN...NONE.  
 
 
 
 
 
UPDATE...10  
DISCUSSION...MMM  
AVIATION...10  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SD Page
The Nexlab MN Page
Main Text Page