136
FXUS63 KFSD 240755
AFDFSD
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
255 AM CDT WED JUN 24 2026
KEY MESSAGES
- ISOLATED SHOWERS WITH A COUPLE RUMBLES OF THUNDER CONTINUE TO
PUSH SOUTHEAST OF THE US HIGHWAY 20 AND IA STATE HIGHWAY 60
CORRIDORS THROUGH DAYBREAK THIS MORNING.
- NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES CONTINUE THROUGH
THE END OF THE WEEK. A COUPLE PASSING SHOWER AND STORM CHANCES
CONTINUE THROUGH THE END OF THE WEEK.
- GROWING POTENTIAL FOR AN EXTENDED PERIOD OF HEAT AND HUMIDITY
BEGINNING SATURDAY, BUT INTENSIFYING SUNDAY INTO NEXT WEEK.
HEAT AND HUMIDITY COULD BRING VERY LOW PROBABILITIES FOR
THUNDERSTORMS EACH DAY.
UPDATE
ISSUED AT 254 AM CDT WED JUN 24 2026
FORECAST REMAINS ON TRACK THIS MORNING.
SHOWERS AND VERY ISOLATED STORMS ARE CONTINUING TO PUSH SOUTH AND
EAST OF THE AREA, LINGERING NEAR US HWY 20 AND EAST OF IA HWY 60.
THESE SHOULD EXIT THE FORECAST AREA BY DAYBREAK. LINGERING CLOUDS
SOUTH OF I-90 MAY BE A BIT SLOWER TO CLEAR THIS MORNING, BUT SHOULD
DECREASE BY MID MORNING.
FOR THE REST OF THE DAY, DRY CONDITIONS PREVAIL THANKS TO SURFACE
HIGH PRESSURE SLIDING SOUTH. DESPITE LOTS OF SUNSHINE TODAY, WE'LL
SEE ANOTHER COOLER THAN AVERAGE DAY WITH HIGHS IN THE 70S THANKS TO
CAA AND NORTHWESTERLY FLOW. THIS AFTERNOON BRINGS GUSTS TO AROUND 25
MPH.
NEXT WAVE MOVES INTO SOUTH CENTRAL SD AND THE SOUTHERN MO VALLEY
LATE THIS AFTERNOON THROUGH TONIGHT. CAN'T RULE OUT SOME SPRINKLES
TO ISOLATED SHOWERS, BUT THINK THAT PRECIPITATION STRUGGLES WITH
LACK OF LOWER LEVEL MOISTURE. INCREASING CLOUDS WITH LOWS IN THE 50S.
DISCUSSION
ISSUED AT 1234 PM CDT TUE JUN 23 2026
THIS AFTERNOON/EVENING: WEAK FRONTAL BOUNDARY CONTINUES TO DRIFT
SOUTHEAST EARLY THIS AFTERNOON. INSTABILITY CONTINUES TO SLOWLY GROW
AHEAD OF THIS BOUNDARY, THROUGH LATEST RAP/HRRR MLCAPE ESTIMATES
CONTINUE TO RANGE BETWEEN 900-1400 J/KG. AS WE REACH CONVECTIVE
TEMPS WE'LL BEGIN TO SEE ISOLATED STRONG OR SEVERE STORMS BY MID-
LATE AFTERNOON. THE INCREASE IN EFFECTIVE WIND SHEAR AOA 40 KNOTS
COULD DRIVE A FEW SLIGHTLY MORE ORGANIZED STORMS, HOWEVER RATHER
MARGINAL MID-LVL LAPSE RATES AND TALL-THIN CAPE PROFILES MAY
INDICATE THE SEVERE RISKS MAY BE MORE LIMITED. ANALOG SOUNDINGS
WOULD SUGGEST HAIL UP TO 1.5" WILL BE POSSIBLE, WITH VERY ISOLATED
STRONGER WIND GUSTS. THE LATEST SSCRAM GUIDANCE ALSO POINTS TO
GREATER HAIL THAN WIND RISKS THROUGH THE HEART OF THE CWA BY MID-
LATE AFTERNOON. THE PERSISTENT DPVA THIS EVENING ALONG WITH
FLATTENING OF THE SURFACE FRONT MAY KEEP SCATTERED SHOWERS AND
EMBEDDED THUNDERSTORMS GOING ALONG OR SOUTH OF I-90 THROUGH THE
EVENING AND INTO THE EARLY OVERNIGHT HOURS (ALONG HIGHWAY 20). THE
SEVERE WEATHER RISK SHOULD DIMINISH QUICKLY BY 7-8PM HOWEVER.
TONIGHT: A LIGHT WIND WILL PERSIST FOR MOST OF THE REGION OVERNIGHT,
WITH A SLIGHTLY INCREASED NORTHWEST WIND DEVELOPING BY DAYBREAK
WEDNESDAY.
WEDNESDAY-THURSDAY: A PAIR OF QUIET DAYS, WITH COOLER TEMPERATURES
CAN BE EXPECTED FOR WEDNESDAY AND THURSDAY AS SURFACE RIDGING MOVES
THROUGH THE REGION. VARIABLE AFTERNOON CU MAY DEVELOP THROUGH THE
REGION WEDNESDAY AFTERNOON AS HIGHS CLIMB INTO THE MIDDLE TO UPPER
70S. LIGHT AND VARIABLE WINDS MAY LEAD TO PATCHY FOG THURSDAY
MORNING, THOUGH WE'LL WATCH FOR SOME HIGH LEVEL CLOUDS DRIFTING
NORTHWARD INTO THE MO RIVER VALLEY THURSDAY MORNING. THIS CLOUD
COVER WILL BE TIED TO A LOW-LVL BAROCLINIC ZONE STRETCHING FROM THE
BLACK HILLS REGION TOWARDS THE OMAHA AREA. TEMPERATURES ONCE AGAIN
REMAIN IN THE MIDDLE TO UPPER 70S.
FRIDAY: A STRONGER MID-LVL WAVE EJECTS OUT OF THE CENTRAL AND
NORTHERN ROCKIES EARLY FRIDAY. THE 00Z ECE/EC CONTINUED TO BE
FOCUSED FURTHER SOUTH THAN THE GEFS/GFS/CMC/CME/NAM WITH THE TRACK
OF THIS WAVE, ASSOCIATED WARM ADVECTION, AND GREATEST POTENTIAL FOR
LIGHT QPF. THAT SAID, THE PROBABILITY FOR MORE THAN 0.10" IS NO MORE
THAN 20-30% IN ANY SOLUTION. BY FRIDAY AFTERNOON, THE ADVANCEMENT
OF A WARM FRONT AND INCREASING EML SHOULD LEAD TO ONLY MINOR RISKS
FOR REDEVELOPMENT BY THE EVENING OVER CENTRAL SOUTH DAKOTA.
SATURDAY-MONDAY: A GENERAL PATTERN EVOLUTION TOWARDS WESTERN CONUS
TROUGHING AND SOUTHEASTERN CONUS RIDGING DEVELOPS QUICKLY SATURDAY.
THIS PATTERN WILL SIGNAL A SHIFT TOWARDS MUCH WARMER TEMPERATURES,
STRONGER EML DEVELOPMENT, AND CONVECTION RISKS GENERALLY DRIVEN BY
THE NEED FOR A TRIGGERING MECHANISM TO OVERCOME THE INHIBITION. MORE
IMPACTFUL WILL BE THE ARRIVAL OF VERY WARM TEMPERATURES.
TEMPERATURES SATURDAY RISE TOWARD THE MIDDLE TO UPPER 80S, HOWEVER
HIGHS WILL ACCELERATE UPWARDS SUNDAY AND MONDAY INTO THE 90S. LATEST
NBM/LREF INDICATE HIGH PROBABILITIES (>70) OF EXCEEDING 90
DEGREES WITH >30-50% PROBABILITIES OF EXCEEDING 95 DEGREES
SUNDAY. ONE THING TO BE AWARE OF IS THE WARM BIAS IN GFS AND
GEFS SURFACE TEMPERATURES AS WE MOVE THROUGH NEXT WEEK WHICH
COULD SKEW BLENDS SLIGHTLY AND PRESENT SOME PRETTY UNREALISTIC
HIGH TEMPERATURE/CAPE PROJECTIONS.
AVIATION /06Z TAFS THROUGH 06Z THURSDAY/
ISSUED AT 1248 AM CDT WED JUN 24 2026
AN AREA OF SHOWERS/EMBEDDED THUNDERSTORMS SOUTH OF I-90 WILL
OCCASIONALLY PRODUCE MVFR-LOCALLY IFR CONDITIONS WITH MODERATE
TO HEAVY RAIN DURING THE PRE-DAWN HOURS. THESE CONDITIONS REMAIN
POSSIBLE AT KSUX UNTIL AROUND 24/07Z. OTHERWISE VFR CONDITIONS
ARE EXPECTED THROUGH THIS TAF PERIOD.
BRIEF WIND GUSTS 20-30KT ARE ALSO POSSIBLE WITH STORMS PRIOR TO
24/10Z. OTHERWISE LIGHT SOUTHWEST TO NORTHWEST WINDS THIS MORNING
WILL OCCASIONALLY GUST 20-25KT THIS AFTERNOON THROUGH SUNSET.
FSD WATCHES/WARNINGS/ADVISORIES
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
UPDATE...SG
DISCUSSION...DUX
AVIATION...JH
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