248  
FXUS63 KABR 020032 AAA  
AFDABR  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE ABERDEEN SD  
732 PM CDT TUE JUL 1 2025  
   
KEY MESSAGES  
 
- SCATTERED SHOWERS AND THUNDERSTORMS (30-50% CHANCE) EXPECTED  
ACROSS THE REGION LATE TONIGHT THROUGH EARLY WEDNESDAY MORNING.  
THERE IS A MARGINAL RISK (LEVEL 1 OUT OF 5) FOR SEVERE WEATHER OVER  
THE MAJORITY OF THE FORECAST AREA. HAIL, UP TO AROUND QUARTER SIZE,  
IS THE MAIN THREAT. WIND GUSTS TO 60 MPH AND BRIEF HEAVY DOWNPOURS  
ARE ALSO POSSIBLE.  
 
- HEAT AND HUMIDITY RETURN TO THE REGION WEDNESDAY THROUGH FRIDAY,  
WITH HIGHS IN THE UPPER 80S AND 90S, AND DEWPOINTS IN THE 60S TO LOW  
70S. HEAT INDICES FLIRTING WITH 100 DEGREES OVER CENTRAL SD.  
 
- A SYSTEM LATE FRIDAY/EARLY SATURDAY WILL BRING RELIEF FROM THE  
HEAT AND HUMIDITY IN THE FORM OF STORMS (60-80% CHANCE EASTERN  
SD/WESTERN MN). MAIN CONCERN IS THE POTENTIAL FOR HEAVY RAINFALL.  
 
 
   
UPDATE  
 
ISSUED AT 728 PM CDT TUE JUL 1 2025  
 
SEE BELOW FOR AN AVIATION FORECAST DISCUSSION FOR THE 00Z TAFS.  
 
 
   
DISCUSSION  
 
ISSUED AT 253 PM CDT TUE JUL 1 2025  
 
THE RIDGE OF HIGH PRESSURE THAT WAS OVER THE AREA TODAY WILL  
SHIFT EASTWARD THIS EVENING WITH THE CENTER OF THE HIGH OVER KS/MO  
BY 00Z. A LEE TROUGH SETS UP ALONG THE EASTERN SIDE OF THE ROCKIES  
NORTHWESTWARD THROUGH MT THROUGH AT LEAST THURSDAY MORNING. ALOFT WE  
CONTINUE ON THE DOWNSTREAM SIDE OF THE RIDGE, IN NORTHWEST FLOW,  
WITH A SHORTWAVE EMBEDDED WITHIN THIS FLOW OVER THE REGION. HOWEVER,  
THE BULK OF THE ENERGY/LIFT WILL BE NEAR ITS SOUTHERN AXIS OVER THE  
SOUTHERN HALF OF SD INTO NE (BETTER CHANCES FOR STRONGER STORMS  
HERE) THIS EVENING AS THE WAVE TRACKS SOUTHEASTWARD THROUGH THE  
MORNING HOURS. A LLJ WILL INCREASE IN STRENGTH LATE TONIGHT WITH  
SPEEDS OUT OF THE SOUTHWEST BETWEEN 25-45KTS WITH THE NORTHERN  
FRINGE OF THIS JET REACHING CENTRAL SD AND WEAKENING THROUGH THE  
EARLY MORNING HOURS. NAM IS A BIT FURTHER NORTH WITH THE LLJ THAN  
GFS/EC WHO KEEP THE NOSE OVER SOUTH CENTRAL SD. THIS SETUP, ALONG  
WITH ONGOING LOW LEVEL MOISTURE/WAA, WILL LEAD TO ELEVATED SHOWERS  
AND THUNDERSTORMS FIRING UP ALONG AND EAST OF THE LEE TROUGH OVER  
THE WESTERN HALF OF SD/NE THIS EVENING, PER HREF/CAMS. THIS  
CONVECTION WILL TRACK SOUTHEAST, ALONG WITH ADDITIONAL DEVELOPMENT  
OF STORMS, LATE TONIGHT INTO THE OVERNIGHT OVER THE AREA. BY 12Z,  
MOST OF THE CONVECTION IS FORECASTED TO EXIT THE CWA WITH MAYBE THE  
LAST OF IT OVER OUR FAR SOUTHEASTERN CWA AS HRRR HOLDS ONTO THIS  
THREAT. MUCAPE WILL RUN BETWEEN 500-1000J/KG AND BULK SHEAR OF 30KTS  
WITH POCKETS OF 40KTS. SOME OF THESE STORMS COULD BE STRONG TO  
SEVERE WITH HAIL AS THE MAIN THREAT, UP TO THE SIZE OF QUARTERS, AND  
WIND GUSTS UP TO 60MPH AS THE SECONDARY THREAT AND BRIEF HEAVY  
DOWNPOURS. THE SPC HAS EXPANDED THE MARGINAL RISK (LEVEL 1 OUT OF 5)  
EASTWARD THAT COVERS MOST OF OUR CWA (WITH THE EXCEPTION OF THE  
EASTERN HALF OF ROBERTS COUNTY INTO MN).  
 
OUR ATTENTION THEN TURNS TO THE END OF THE WEEK INTO SATURDAY AS THE  
NORTHERN PLAINS WILL BE ON THE UPSTREAM SIDE OF THE RIDGE/DOWNSTREAM  
OF A TROUGH IN SOUTHWEST FLOW ALL THE WAY TO THE SURFACE. HOWEVER,  
WINDS ALOFT WILL BE QUITE WEAK RANGING BETWEEN 20-30KTS. LEE  
TROUGHING CONTINUES OVER THE WESTERN DAKOTAS WHICH LIES SOUTH OF A  
LOW PRESSURE SYSTEM THAT WILL BE OVER ~CENTRAL MANITOBA/SASKATCHEWAN  
BORDER BY 12Z THURSDAY. THIS LOW IN CANADA SHIFTS EAST (AND SURFACE  
TROUGH) WITH A SECONDARY LEE LOW FORMING AND PUSHING NORTHEAST AND  
OVER CENTRAL ND BY 12Z FRIDAY. THE LOW IN CANADA WILL CONTINUE TO  
TRACK EASTWARD AND THE SECONDARY LOW SOUTHEASTWARD INTO MN THROUGH  
SATURDAY MORNING. BEING IN THE WARM SECTOR, WITH SOUTH TO SOUTHWEST  
WINDS FROM THE SURFACE TO 500MB, WILL BRING IN ONGOING WARM AND  
MOIST AIR AS DEWPOINTS WILL RANGE WELL INTO THE UPPER 60S TO THE  
LOWER 70S AND 12-16C AT 850MB WITH THESE VALUES HIGHEST OVER THE  
EASTERN HALF THE CWA BY FRIDAY AFTERNOON AND EVENING. THIS SYSTEM  
WORKING WITH THE WARM AND MOIST AIR WILL LEAD TO SHOWERS AND  
THUNDERSTORMS DEVELOPING OVER THE CWA FRIDAY THROUGH SATURDAY WITH  
THE HIGHEST POPS OF 60 TO 80% JAMES RIVER VALLEY AND EASTWARD FRIDAY  
EVENING THROUGH EARLY SATURDAY WHERE THIS BETTER MOISTURE AND  
FORCING LIES.  
 
NAEFS INDICATES PWAT VALUES ABOUT 2 TO 2.5 STANDARD DEVIATIONS ABOVE  
CLIMO WITH VALUES UP TO 1.50-1.75" FRIDAY EVENING THROUGH SATURDAY  
MORNING EAST OF THE MO RIVER. WITH WEAK FLOW ALOFT AND LOTS OF  
MOISTURE IN THE ATMOSPHERE, HEAVY RAIN LOOKS TO BE THE MAIN THREAT  
WITH THE SHOWERS AND THUNDERSTORMS ESPECIALLY ANY STORMS THAT ARE  
SLOW MOVING AND/OR TRAINING OVER THE SAME AREA THAT COULD LEAD TO  
AREAL FLOODING OR FLASH FLOODING POTENTIAL. ERO OUTLOOK INDICATES A  
MARGINAL RISK OVER OUR EASTERN CWA DUE TO THIS POTENTIAL WHERE THIS  
AREA HAS ALREADY RECEIVED SEVERAL INCHES OF RAIN/FLOODING OVER THE  
PAST COUPLE OF WEEKS. ALONG AND EAST OF THE MO RIVER MEAN CAPE, PER  
MODEL BLEND OF ENS/GEFS/GEPS, SHOW VALUES BETWEEN 1000-2000J/KG WITH  
MUCAPE IN EXCESS OF 2,000J/KG JAMES RIVER VALLEY AND EASTWARD FRIDAY  
AFTERNOON AND EVENING WITH BULK SHEAR PRETTY WEAK BETWEEN 15-20KTS.  
SO THIS WEAK SHEAR AND LACK OF LIFT ALOFT MAY PUT A DAMPER ON  
WIDESPREAD SEVERE WEATHER (OR KEEP IT ISOLATED)AS THE HIGHER SHEAR  
MOVES IN BEHIND THE SYSTEM AND DISPLACED FROM THE BETTER INSTABILITY  
AHEAD OF THE COLD FRONT.  
 
IT WILL BE HOT AND MUGGY WEDNESDAY THROUGH FRIDAY WITH TEMPS IN THE  
UPPER 80S TO THE UPPER 90S AND DEWPOINTS IN THE MID TO UPPER 60S TO  
LOWER 70S. THE HOTTEST DAY IS FORECASTED TO BE THURSDAY WITH HIGHS  
WELL IN THE 90S TO MAYBE EVEN 100 DEGREE READINGS OVER CENTRAL SD.  
HEAT RISK IS IN THE MODERATE TO MAJOR CATEGORY THURSDAY, WITH THE  
MAJOR CATEGORY WEST OF THE JAMES RIVER. HEAT RISK WILL MAINLY BE IN  
THE MODERATE CATEGORY (WITH A FEW PATCHES OF MAJOR OVER KABR AND  
KATY AREA) FRIDAY. THIS COLD FRONT WILL BRING RELIEF TO THE HEAT AND  
HUMIDITY WITH TEMPS BACK IN THE 70S/80S AND DEWPOINTS BACK IN THE  
50S TO LOWER 60S. OTHERWISE CLUSTERS INDICATES ZONAL FLOW ALOFT THIS  
WEEKEND IN A ONGOING -PNA PATTERN CHANGING TO A -PNA/SPLIT FLOW  
PATTERN EARLY NEXT WEEK. THIS LEADS TO SEVERAL PASSING SHORTWAVES  
OVER THE AREA AND ONGOING CHANCES OF PRECIP THROUGH AT LEAST  
TUESDAY. A RIDGE LOOKS TO BUILD OVER THE WESTERN CONUS/ROCKIES FOR  
THE MIDDLE OF NEXT WEEK.  
 
 
   
AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/  
 
ISSUED AT 728 PM CDT TUE JUL 1 2025  
 
TERMINALS KABR,KATY,KPIR,KMBG  
 
VFR CONDITIONS ARE FORECAST FOR THE TAF PERIOD, OUTSIDE OF  
CONVECTION EXPECTED LATER TONIGHT (VISBY MAY BE REDUCED IN HEAVIER  
DOWNPOURS). HIGH PRESSURE WILL CONTINUE TO SHIFT SOUTHEAST  
OVERNIGHT WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS  
DEVELOPING OVER PORTIONS OF CENTRAL AND NORTHEAST SOUTH DAKOTA  
TONIGHT. THESE STORMS WILL SPREAD/MOVE SOUTHEAST THROUGH EARLY  
WEDNESDAY MORNING. CONTINUED TO USE PROB30 TO ADDRESS THIS  
POTENTIAL.  
 
 
   
ABR WATCHES/WARNINGS/ADVISORIES  
 
SD...NONE.  
MN...NONE.  
 
 
 
 
UPDATE...10  
DISCUSSION...MMM  
AVIATION...10  
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