618  
FXUS63 KUNR 091115  
AFDUNR  
 
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY  
NATIONAL WEATHER SERVICE RAPID CITY SD  
515 AM MDT WED JUL 9 2025  
   
KEY MESSAGES  
 
-ISOLATED TO SCATTERED THUNDERSTORMS CONTINUE OVER THE NEXT  
COUPLE DAYS, SOME OF WHICH MAY BE STRONG TO SEVERE TODAY,  
ESPECIALLY THIS AFTERNOON IN WESTERN SOUTH DAKOTA  
 
-HOT TODAY, WITH MODERATING TEMPS THROUGH THE WEEKEND BEHIND A  
COLD FRONT  
 
-MAINLY DRY THIS WEEKEND WITH UNSETTLED CONDS POSSIBLE AGAIN NEXT  
WEEK  
 
 
   
DISCUSSION  
(TODAY THROUGH TUESDAY)  
ISSUED AT 123 AM MDT WED JUL 9 2025  
 
MEAN WNW FLOW ALOFT WILL CONTINUE, SUPPORTING NEAR DAILY IMPULSES  
THROUGH THE REGION THE NEXT FEW DAYS. A STRONGER SYSTEM WILL  
FORCE A COLD FRONT THROUGH THE REGION THURSDAY NIGHT, WITH THINGS  
COOLING DOWN FRIDAY AND MAINLY DRY WEATHER THIS WEEKEND. WEAK  
IMPULSE CURRENTLY SUPPORTING ELEVATED POS THETA-E ADV ACROSS  
SCENTRAL SD THIS MORNING. EXPECT ISOLD TS TO CONTINUE THERE,  
SHIFTING EAST THROUGH EARLY MORNING. A FEW STRONGER CELLS ARE  
POSSIBLE, SUPPORTING HAIL AND GUSTY WINDS. LEE-SIDE TROUGH WILL  
SLOWLY PUSH INTO THE REGION TODAY AND WILL PROVIDE THE FOCUS FOR  
SCT SHRA AND TS THIS AFTERNOON, IN ADDITION TO EXPECTED CONVECTION  
OVER THE BLACK HILLS. WEAKLY CAPPED ENVIRONMENT WITH ABUNDANT LL  
MOISTURE WILL BE IN PLACE AHEAD OF THE TROUGH, WITH WEAK FORCING  
ALOFT PROVIDING THE ADDITIONAL SUPPORT NEEDED TO FIRE CONVECTION.  
ML CAPE OF 1500-3000 J/JG WILL BE ENOUGH FOR ISOLD STRONG TO  
SEVERE STORMS WHEN COUPLED WITH INCREASING SHEAR AS A JETLET  
ADVECTS INTO THE REGION LATER. STORMS WILL SHIFT EAST THIS  
EVENING. HOWEVER, ANOTHER ROUND OF ELEVATED POS THETA-E ADV WILL  
SUPPORT SLIGHT CHANCES FOR TS OVERNIGHT ACROSS MUCH OF THE AREA,  
ALTHOUGH THERE WOULD LIKELY BE BANDING IN CELLS WHERE THE NOSE OF  
THE STRONGEST ADVECTION OCCURS. ANOTHER SLUG OF MONSOON MOISTURE  
WILL ADVECT OVER THE REGION THURS AHEAD OF A STRONGER IMPULSE.  
THIS COMBINED WITH RESIDUAL LL MOISTURE WILL SUPPORT ANOTHER ROUND  
OF SCT-ISOLD TS THURS AFTERNOON AND EVENING, WITH THE BULK OF  
CONVECTION SHIFTING INTO CENTRAL AND EASTERN SD IN THE EVENING.  
BREEZY NW WINDS WILL DEVELOP BEHIND THE COLD FRONT THUR NIGHT WITH  
COOLING AND DRYING ONGOING. RESIDUAL MOISTURE MAY FORCE A FEW  
SHOWERS/STORMS OVER THE FAR SW FRIDAY, BUT MOST PLACES WILL  
PROBABLY END UP DRY. MAINLY SUNNY AND DRY THIS WEEKEND, ALTHOUGH  
RETURN FLOW MAY SUPPORT CONVECTION BY SUNDAY OVER THE FAR WEST.  
UNSETTLED FLOW THEN LOOKS TO RETURN NEXT WEEK AS A BAROCLINIC ZONE  
STALLS NEAR OR OVER THE REGION WITH SUFFICIENT MOISTURE AND FAST  
FLOW ALOFT.  
 
 
   
AVIATION  
(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)  
ISSUED AT 511 AM MDT WED JUL 9 2025  
 
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THE EXCEPTION  
WOULD BE MVFR CONDITIONS WITH ANY STORMS THAT DEVELOP THIS  
AFTERNOON.  
 
 
   
UNR WATCHES/WARNINGS/ADVISORIES  
 
SD...NONE.  
WY...NONE.  
 
 
 
 
DISCUSSION/KEY MESSAGES...JC  
AVIATION...JC  
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