294
FXUS63 KFSD 110806
AFDFSD
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
306 AM CDT SAT JUL 11 2026
KEY MESSAGES
- PATCHY AND LOCALLY DENSE FOG NEAR AND EAST OF I-29 WILL LEAD
TO VISIBILITY BELOW TWO MILES AT TIMES THROUGH MID MORNING;
WIDESPREAD DENSE FOG IS NOT EXPECTED. BE PREPARED FOR QUICKLY
CHANGING VISIBILITY IF TRAVELING.
- HOT AND DRY CONDITIONS RETURN TODAY AND CONTINUE THROUGH NEXT WEEK.
- DAILY HEAT INDEX VALUES REMAIN UNDER 100 DEGREES FOR MOST
AREAS, BUT THE CUMULATIVE NATURE OF THE HEAT COULD LEAD TO
INCREASING POTENTIAL FOR HEAT-RELATED ISSUES.
- NEXT CHANCES FOR RAIN COULD RETURN BY LATE WEEK. HOWEVER,
SEVERE WEATHER IS NOT EXPECTED AT THIS TIME.
UPDATE
ISSUED AT 305 AM CDT SAT JUL 11 2026
PATCHY AND LOCALLY DENSE FOG HAS DEVELOPED THIS MORNING, MAINLY NEAR
AND EAST OF I-29. LOWEST VISIBILITY SO FAR HAS BEEN NEAR US HWY 71
IN NORTHWESTERN IA, WHERE A COUPLE OF SITES HAVE BRIEFLY DROPPED TO
AND BELOW A MILE. NOT CURRENTLY EXPECTING WIDESPREAD DENSE FOG, BUT
WILL MONITOR TRENDS - ESPECIALLY ACROSS NORTHWESTERN IA WHERE WINDS
ARE VERY LIGHT TO CALM. TEMPERATURES THIS MORNING ARE IN THE UPPER
50S TO THE LOWER 70S WITH CLEAR SKIES.
MAIN STORY REMAINS THE HEAT WITH RIDGING BUILDING ALOFT. TODAY
BRINGS HIGHS IN THE MID 80S (EAST) TO THE MID 90S (WEST). DRY
CONDITIONS PREVAIL WITH LIGHT SOUTHERLY WINDS. HEAT INDEX VALUES
REMAIN IN THE UPPER 80S TO MID 90S WITH LOWER HUMIDITY ACROSS THE
AREA. CONFIDENCE REMAINS HIGH REGARDING CONTINUED ABOVE AVERAGE
TEMPERATURES (HIGHS IN THE 90S TO LOWER 100S) THROUGH AT LEAST MID
NEXT WEEK, BUT HUMIDITY MAY CONTINUE TO LIMIT HEAT INDEX VALUES TO
BELOW HEADLINE CRITERIA. THAT SAID, WARM OVERNIGHT LOWS AND EXTENDED
HEAT COULD LEAD TO HEAT IMPACTS, ESPECIALLY FOR VULNERABLE
POPULATIONS OR THOSE SPENDING TIME OUTDOORS.
DISCUSSION
ISSUED AT 1253 PM CDT FRI JUL 10 2026
THIS AFTERNOON AND NIGHT: CONSIDERABLE MID-UPPER CLOUD COVER FROM
MID-LVL VORTICITY OVER EASTERN NEBRASKA CONTINUES TO SPREADS
ACROSS THE CWA EARLY THIS AFTERNOON. HIGH RESOLUTION GUIDANCE
KEEPS THIS CLOUD COVER SPREAD OVER THE EASTERN HALF OF THE TRI-
STATE AREA INTO EARLY EVENING. DEPENDING ON THE THICKNESS OF
THIS LAYER, TEMPERATURES COULD BE HAMPERED SLIGHTLY. FURTHER
NORTH, WE CONTINUE TO SEE A COMPACT AREA OF VORTICITY CROSS
WESTERN AND SOUTHWESTERN MINNESOTA WITH A BIT OF ACCAS NEARBY.
WHILE SOME SPRINKLES MAY DEVELOP WITH THIS ACCAS, DEEPER
DEVELOPMENT REMAINS LESS LIKELY GIVEN WEAKER INSTABILITY IN THE
AREA.
WHILE THE HIGH LEVEL CLOUDS ADD SOME UNCERTAINTY, GUIDANCE HAS
GENERALLY BACKED OFF ON CONVECTIVE POTENTIAL LATER THIS AFTERNOON
AND EVENING. LIKELY DUE TO A LACK OF ANY STRONG SURFACE CONVERGENCE
AND A BIT OF WEAK INHIBITION. I CONTINUE TO SEE TWO AREAS TO
WATCH...ONE BEING WITH THE ACCAS FIELD NEAR WATERTOWN, BUT
SECOND ALONG WHAT MIGHT BE WHERE A WEAK SURFACE CONVERGENCE
BOUNDARY DEVELOPS BY MID-LATE AFTERNOON FROM DESMET TO MITCHELL
AND YANKTON. INSTABILITY IN THIS AREA WILL RUN FROM 1500-2000
J/KG, BUT SHEAR IS VERY WEAK. THIS RESULTS IN ONLY PULSE SEVERE
STORMS WITH QUARTERS AND VERY LOCALIZED 60 MPH WINDS.
ISOLATED CONVECTION MAY CONTINUE OVER CENTRAL AND WEST CENTRAL
MINNESOTA OVERNIGHT, BUT FURTHER SOUTHWEST WE'LL REMAIN QUIET WITH
LIGHT WINDS. SOME FOG MAY POP UP, BUT WIDESPREAD DENSE FOG ISN'T
ANTICIPATED.
THIS WEEKEND: A QUIET WEEKEND IS AHEAD AS TEMPERATURES BEGIN TO
SLOWLY RISE. WINDS WILL TURN TO THE SOUTH OR SOUTHEAST BOTH
SATURDAY AND SUNDAY. HIGH TEMPERATURES BOTH DAYS WILL REACH INTO
THE UPPER 80S OVER MN/IA AND INTO THE MIDDLE TO UPPER 90S WEST OF I-
29. HEAT INDEX VALUES REMAIN BELOW ADVISORY CRITERIA.
NEXT WEEK: A 600 DM RIDGE WILL CENTER ITSELF OVER THE NORTHERN
PLAINS FOR MOST OF NEXT WEEK. THIS PATTERN SPELLS TWO THING...HOT
AND DRY. EACH DAY WILL FEATURE NEARLY THE SAME IDENTICAL SETUP,
WITH A BREEZY SOUTHERLY TO SOUTHEASTERLY WIND AND PLENTY OF
SUNSHINE. THE RESULTING HIGH TEMPERATURES REACH THE LOWER TO MIDDLE
90S ALONG AND EAST OF I-29, WITH TEMPERATURES SOARING TOWARDS THE
100 DEGREE MARK. ECE/GEFS PROBABILITIES SHOW 40+ PROBABILITIES OF
>100 DEGREE HIGHS ALONG THE JAMES RIVER VALLEY. THE SAVING GRACE
THIS WEEK WILL BE THE PERSISTENT DRY AIR ALOFT AND BREEZY WINDS. THE
RESULTANT MIX DOWN EACH AFTERNOON WILL DROP THE DEW POINTS TOWARDS
THE 50S AND LOWER 60S. THIS RESULTS IN A LOWER HEAT INDEX TREND,
WITH ONLY ISOLATED SPOTS WITH A HEAT INDEX VALUE NEAR 100. WHILE WE
WON'T REACH ADVISORY CRITERIA IN MOST AREAS, THE CUMULATIVE NATURE
OF THE DAILY HEAT AND SLOWER FALL IN OVERNIGHT LOWS COULD STILL LEAD
TO SOME HEALTH RELATED ISSUES.
AVIATION /06Z TAFS THROUGH 06Z SUNDAY/
ISSUED AT 1124 PM CDT FRI JUL 10 2026
MAINLY VFR CONDITIONS WILL CONTINUE THIS TAF PERIOD. TAKING A
LOOK AT SATELLITE IMAGERY, MOST CLEAR CONDITIONS CONTINUE THIS
EVENING. AS WINDS CONTINUE TO LIGHTEN, SOME HIGH RESOLUTION
GUIDANCE HAS STARTED TO HINT AT AREAS OF MVFR TO LIFR FOG
DEVELOPING CLOSER TO DAYBREAK MAINLY ACROSS NORTHWESTERN IA. AS
A RESULT, DECIDED TO ADD A TEMPO GROUP TO THE KSUX TAF TO
CAPTURE THE INCREASING PROBABILITIES. OTHERWISE, LIGHT AND
VARIABLE WINDS OVERNIGHT WILL BECOME MORE SOUTHERLY INTO
SATURDAY WITH MARGINALLY BREEZY WINDS POSSIBLE AT TIMES.
FSD WATCHES/WARNINGS/ADVISORIES
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
UPDATE...SG
DISCUSSION...DUX
AVIATION...05
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