736
FXUS63 KFSD 200212
AFDFSD
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
912 PM CDT FRI JUN 19 2026
KEY MESSAGES
- GREATEST SEVERE WEATHER THREAT REMAINS FOCUSED SOUTH OF THE
MISSOURI RIVER SATURDAY.
- MODELS ARE A BIT MORE CONSISTENT ON KEEPING THE HEAVIER RAIN
SOUTH OF THE MISSOURI RIVER AS WELL. THE PROBABILITY FOR AN
INCH OF RAIN ABOUT 30-50 PERCENT ALONG THE MISSOURI RIVER AND
CLOSER TO 10 TO 20 PERCENT ALONG I-90.
- BELOW NORMAL TEMPERATURES AND PERIODIC RAIN CHANCES WILL
CONTINUE INTO THE START OF NEXT WEEK. SEVERE WEATHER CHANCES
WILL BE LOW.
UPDATE
ISSUED AT 904 PM CDT FRI JUN 19 2026
ANOTHER COOL JUNE NIGHT IS AHEAD FOR THE AREA AS WINDS TURN
LIGHT TO CALM AND TEMPERATURES DROP TO THE UPPER 40S TO LOWER
50S. PATCHY FOG IS POSSIBLE TONIGHT/EARLY TOMORROW MORNING GIVEN
THE LIGHT WINDS AND MAINLY CLEAR SKIES EXPECTED; HOWEVER, THE
EXTENT OF FOG MAY BE LIMITED BY THE FACT THAT NORTHWESTERLY LOW
LEVEL FLOW WILL BE USHERING IN RELATIVELY DRIER AIR INTO THE
AREA. WITH THAT, THE BETTER CHANCES (AROUND 30-40%) WILL BE OVER
NORTHWEST IOWA AND NEARBY AREAS OF SOUTHWEST MINNESOTA AND
SOUTHEAST SOUTH DAKOTA WHERE COOLER TEMPERATURES FROM TODAY'S
RAIN/CLOUDS MEANS LESS OF A WAYS TO GO FOR THE TEMPERATURE TO
DROP TO THE DEW POINTS. BUT AGAIN, THESE AREAS WILL ALSO BE
FIGHTING THAT DRIER FLOW AND THIS LENDS TO THAT LOWER TO MEDIUM
CONFIDENCE IN FOG DEVELOPMENT.
DRY CONDITIONS ARE EXPECTED FOR MOST OF THE AREA FOR THE DAYTIME
HOURS ON SATURDAY, BUT RAIN AND STORM CHANCES WILL BEGIN TO INCREASE
THROUGH THE MID AFTERNOON NEAR AND SOUTH OF THE MISSOURI RIVER
VALLEY CORRIDOR AS A WARM FRONT NUDGES TOWARDS THE AREA. PLENTY OF
SHEAR, BUT LIMITED INSTABILITY AND MODEST MID LEVEL LAPSE RATES MAKE
SEVERE WEATHER UNLIKELY. HIGHS WILL GENERALLY BE IN THE MID 70S TO
LOW 80S SATURDAY, BUT DEPENDING ON WHETHER OR NOT SHOWERS
ARRIVE PRIOR TO OR RIGHT AROUND PEAK DAYTIME HEATING, COOLER
HIGHS IN THE LOW 70S ARE POSSIBLE IN SOUTH-CENTRAL SOUTH DAKOTA.
DISCUSSION
ISSUED AT 134 PM CDT FRI JUN 19 2026
SHOWERS WILL EXIT THE AREA LATE THIS AFTERNOON AS THE WEAK WAVE
PUSHES EAST. RAINFALL AMOUNTS CONTINUE TO REMAIN ON THE LIGHT SIDE.
A VERY SMALL CHANCE FOR AN ISOLATED SHOWER/THUNDERSTORM IN
SOUTHWEST MN THIS EVENING. IF SOMETHING CAN DEVELOP A WIND GUST TO
40 MPH WILL BE POSSIBLE. OTHERWISE, BEHIND THE WEAK WAVE THAT
BROUGHT THESE SHOWERS, SURFACE HIGH PRESSURE WILL NUDGE INTO THE
AREA WITH TEMPERATURES EXPECTED TO FALL INTO THE UPPER 40S TO LOWER
50S ON SATURDAY MORNING.
SATURDAY LOOKS DRY AND MILD WITH LIGHT WINDS. AFTER THE COOL
MORNING STARTS, HIGHS SHOULD MOSTLY BE IN THE 70S.
SATURDAY NIGHT INTO SUNDAY WILL SEE UPPER LEVEL LOW PRESSURE SETTLE
INTO THE AREA WITH BROAD LOW TO MID LEVEL WARM AIR ADVECTION LOCKING
INTO PLACE. OVERALL THE INSTABILITY IS ON THE WEAK SIDE SO SEVERE
WEATHER CHANCES REMAIN VERY LOW. EVEN THE HEAVY RAIN THREAT IS
PRETTY MUTED, WITH MAINLY THE MISSOURI RIVER AREA SEEING A CHANCE
FOR AN INCH OR MORE OF RAINFALL INTO MONDAY MORNING. GIVEN THE VERY
DRY CONDITIONS WILL NEED TO SEE MUCH MORE THEN 1-2" OF RAIN OVER A 24
TO 36 HOUR PERIOD TO HAVE ANY CONCERN FOR FLOODING OR FLASH
FLOODING. AND GIVEN THE EXPECTED WEAKER INSTABILITY, BRIEF RAINFALL
RATES OF 2-4" PER HOUR ALSO SEEM VERY UNLIKELY.
NEXT WEEK WILL SEE CONTINUED NORTHWEST FLOW ALOFT WHICH WILL LIMIT
ANY INSTABILITY THAT CAN BUILD INTO THE AREA. THERE WILL BE A FEW
WAVES THAT MOVE THROUGH THE AREA IN THIS NORTHWEST FLOW, BUT THE
THREAT FOR HEAVY RAIN AND SEVERE WEATHER WILL BE LOW. THIS NORTHWEST
FLOW WILL ALSO KEEP COOLER CONDITIONS IN PLACE WITH BELOW NORMAL
TEMPERATURES EXPECTED EACH DAY.
AVIATION /00Z TAFS THROUGH 00Z SUNDAY/
ISSUED AT 628 PM CDT FRI JUN 19 2026
WINDS LOOK TO QUICKLY DIMINISH THROUGH THIS EVENING, BECOMING
LIGHT TO CALM OVERNIGHT. SKIES WILL BE MOSTLY CLEAR, BUT
THINKING THERE WILL BE ENOUGH CLOUD COVER TO PREVENT WIDESPREAD
FOG DEVELOPMENT DESPITE RECENT RAINFALL. HOWEVER, PATCHY FOG
CAN'T BE RULED OUT (AROUND 30% CHANCE) MAINLY SOUTH OF HIGHWAY
14 EARLY SATURDAY MORNING. NOT ENOUGH CONFIDENCE IN FORMATION
AND COVERAGE OF FOG TO INCLUDE MENTION IN THE TAFS AT THIS TIME.
RAIN CHANCES LOOK TO INCREASE ALONG AND SOUTH OF THE MISSOURI
RIVER VALLEY BY AFTERNOON SATURDAY, BRINGING MVFR CIGS TO MAINLY
SOUTH-CENTRAL SOUTH DAKOTA TO END THE PERIOD. WINDS WILL BE
MAINLY LIGHT THROUGH THE DAY SATURDAY WITH THE EXCEPTION OF
SOUTH-CENTRAL SOUTH DAKOTA WHERE SOUTHEASTERLY GUSTS APPROACHING
20-25 KTS WILL BE POSSIBLE IN THE AFTERNOON.
FSD WATCHES/WARNINGS/ADVISORIES
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
UPDATE...SAMET
DISCUSSION...08
AVIATION...SAMET
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page