730
FXUS63 KUNR 031851
AFDUNR
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1251 PM MDT WED JUN 3 2026
KEY MESSAGES
- SEVERE THUNDERSTORM RISK ACROSS SOUTH CENTRAL SD THIS AFTERNOON
AND EVENING WITH LARGE HAIL AND DAMAGING WINDS AS THE PRIMARY
THREATS, THOUGH A TORNADO CAN'T BE RULED OUT.
- CHANCE OF SEVERE WEATHER WITH ALL HAZARDS POSSIBLE THURSDAY.
- WARMING TEMPERATURES EXPECTED INTO THE WEEKEND.
DISCUSSION
(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 1250 PM MDT WED JUN 3 2026
VISIBLE SATELLITE SHOWS CLOUD COVER OVER MUCH OF WESTERN SD WITH
ONGOING STORMS OVER NORTH CENTRAL SD. SKIES HAVE CLEARED OUT OVER
WYOMING AND THE BLACK HILLS WITH WATER VAPOR IMAGERY SHOWING
NARROW PLUME OF MID LEVEL MOISTURE STREAMING INTO SOUTH CENTRAL
SD. SFC COLD FRONT MAKES ITS WAY ACROSS THE EASTERN TIER OF THE
CWA THROUGH THIS AFTERNOON AND EVENING. PLUME OF 50-60F DEWPOINTS
AND MODERATE INSTABILITY OF 2000-3000 J/KG SB CAPE WILL SUPPORT
THUNDERSTORM DEVELOPMENT ALONG THE FRONT. MID-LEVEL FLOW WILL
STRENGTHEN AS THE SHORTWAVE APPROACHES WITH DEEP LAYER SHEAR
INCREASING TO 30-40 KTS WHICH WILL SUPPORT ORGANIZED CONVECTION
AND ROTATING UPDRAFTS. CAMS ARE ONCE AGAIN STRUGGLING WITH TIMING
AND STORM MODE WITH THE HRRR CONTINUING TO PUSH BACK DEVELOPMENT
OVER SOUTH CENTRAL SD UNTIL LATER THIS EVENING (AFTER 6 TO 7 PM)
WHILE THE NAM AND RRFS BOTH SHOW STORMS DEVELOPING SOMEWHAT
EARLIER (AROUND THE 4 TO 5 PM MDT TIMEFRAME). STORMS MAY START OFF
AS DISCRETE CELLS, CAPABLE OF LARGE HAIL, DAMAGING WINDS, AND A
LOW TORNADO RISK. STORMS WILL QUICKLY COALESCE INTO A LINE AS THE
FRONT PUSHES THROUGH WITH THE PRIMARY THREAT TRANSITIONING TO
DAMAGING WIND GUSTS.
ATTENTION TURNS TO TOMORROW WHERE SEVERE THUNDERSTORMS ARE ONCE
AGAIN POSSIBLE ACROSS MUCH OF THE FORECAST AREA. ANOTHER SHORTWAVE
MOVING ALONG NEARLY ZONAL FLOW WILL EJECT OVER THE NORTHERN
PLAINS BY THE AFTERNOON HOURS. STRENGTHENING MID LEVEL FLOW WILL
SUPPORT DEEP LAYER SHEAR VALUES OF 30 TO 40 KTS WITH SBCAPE VALUES
CLIMBING TO 2000-3000+ J/KG WITH THE HIGHEST VALUES ACROSS
SOUTHWESTERN SD. THIS LOOKS TO BE A TYPICAL NORTHERN BLACK HILLS
SUPERCELL ENVIRONMENT, CAPABLE OF VERY LARGE HAIL (2+"), THOUGH A
TORNADO OR TWO CAN'T BE ENTIRELY RULED OUT. AS STORMS PUSH
EASTWARD OVER THE PLAINS THROUGH THE EVENING HOURS, THEY MAY
TRANSITION INTO AN MCS WITH ASSOCIATED SEVERE WIND THREAT.
THINGS SETTLE DOWN FOR MOST OF THE CWA FRIDAY AS SHORTWAVE
RIDGING BUILDS TO OUR WEST. STORMS ARE STILL POSSIBLE OVER SOUTH-
CENTRAL SD AS THE SFC FRONT AND SHORTWAVE EXIT THE REGION. IN
ADDITION, DIURNALLY DRIVEN SHOWERS CAN'T BE RULED OUT OVER THE
BLACK HILLS IN THE AFTERNOON. SHORTWAVE RIDGE WILL MOVE OVER THE
REGION BY SATURDAY AND BRING HOT AND DRY CONDITIONS TO THE CWA.
STORM CHANCES RETURN SUNDAY AS UPPER LEVEL TROF DEEPENS OVER THE
WESTERN US AND PLACES OUR CWA UNDER UNSETTLED SOUTHWEST FLOW.
AVIATION
(FOR THE 18Z TAFS THROUGH 18Z THURSDAY)
ISSUED AT 1127 AM MDT WED JUN 3 2026
LOW CEILINGS WILL CONTINUE TO BURN OFF IN NORTHEAST WY AND EAST
OF THE BLACK HILLS OVER THE NEXT HOUR OR SO. AFTER WHICH, VFR
CONDITIONS ARE EXPECTED AT BOTH TAF SITES UNTIL EARLY THURSDAY
MORNING (~12Z). LOW CLOUDS WILL REDEVELOP ACROSS THE AREA,
BRINGING BACK MVFR/IFR CONDITIONS.
UNR WATCHES/WARNINGS/ADVISORIES
SD...NONE.
WY...NONE.
DISCUSSION/KEY MESSAGES...WONG
AVIATION...SCHWEIGERT
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page