060  
FXUS63 KFSD 250435  
AFDFSD  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE SIOUX FALLS SD  
1035 PM CST SAT FEB 24 2024  
   
KEY MESSAGES
 
 
- NEAR RECORD WARMTH ON MONDAY WITH HIGHS AROUND 30 DEGREES  
ABOVE NORMAL. BREEZY WINDS AND MODERATE-LOW HUMIDITY LEVELS  
RESULT IN HIGH TO VERY HIGH FIRE DANGER.  
 
- A STRONG COLD FRONT PUSHES SOUTHEAST LATE MONDAY NIGHT-  
TUESDAY MORNING, FOLLOWED BY GUSTY NORTHWEST-NORTH WINDS,  
FALLING DAYTIME TEMPERATURES AND LOW TO MODERATE CHANCES  
(20-40%) FOR SNOW/RAIN. CONFIDENCE IN FRONTAL TIMING AND  
RESULTANT TEMPERATURES IS MODERATE.  
 
- BRIEF COOL-DOWN CONTINUES WEDNESDAY WITH SLIGHTLY BELOW NORMAL  
TEMPERATURES POSSIBLE, BUT MILD TEMPERATURES RETURN FOR THE  
END OF THE WEEK.  
 

 
   
DISCUSSION
 
 
ISSUED AT 233 PM CST SAT FEB 24 2024  
 
TONIGHT-SUNDAY: QUIET AND MILD WEATHER CONTINUES THROUGH THE REST OF  
THIS WEEKEND, THOUGH NOT QUITE AS WARM AS TODAY IN SOME LOCATIONS AS  
A WEAK BACKDOOR COOL FRONT SAGS INTO FAR NORTHERN PORTIONS OF THE  
AREA ON SUNDAY. PREDOMINANT WESTERLY FLOW TONIGHT WILL KEEP TEMPS ON  
THE MILD SIDE, WITH LOWS IN THE UPPER 20S-MID 30S. THE WESTERLY FLOW  
CONTINUES SUNDAY, INCREASING WITH AFTERNOON GUSTS 20-25MPH. DESPITE  
THE COOLING LOW LEVELS NORTH OF I-90, DECENT MIXING IN THE WESTERLY  
FLOW SHOULD STILL ALLOW FOR HIGHS IN THE 50S, WITH SOME LOWER 60S  
TOWARD THE MISSOURI RIVER VALLEY.  
 
MONDAY: STRONG WARMING BUILDS INTO THE REGION SUNDAY NIGHT-MONDAY,  
AHEAD OF A STRONGER UPPER TROUGH/COLD FRONT WHICH WILL MOVE ACROSS  
THE REGION MONDAY NIGHT-TUESDAY. DECENT MODEL CONSENSUS SHOWING  
850MB TEMPS EXCEEDING +10C BUILDING INTO SOUTHERN PARTS OF THE  
FORECAST AREA BY LATE MONDAY, AGAIN WITH A FAVORABLE SOUTHWEST LOW  
LEVEL FLOW FOR STRONG MIXING. DID NUDGE TEMPS UP SLIGHTLY FROM THE  
STRAIGHT NBM BY BLENDING IN THE 90TH PERCENTILE VALUES, AS THESE  
850MB TEMPS WOULD SUPPORT LOWER 70S THROUGH AT LEAST THE MISSOURI  
RIVER VALLEY. WILL COME CLOSE TO SOME LONG-STANDING RECORD HIGHS  
(LISTED BELOW), AS WELL AS RECORD WARM LOWS, THOUGH CONFIDENCE IN  
BREAKING RECORDS IS LOW (~30%).  
 
CURRENT RECORD HIGH TEMPERATURES FOR FEBRUARY 26TH:  
KFSD: 66/1896  
KSUX: 75/1896  
KHON: 68/1896  
KMHE: 69/1896  
 
MONDAY NIGHT-TUESDAY: A STRONG COLD FRONT PUSHES SOUTHEAST THROUGH  
THE REGION LATE MONDAY NIGHT THROUGH TUESDAY MORNING. STILL SEEING  
SOME INCONSISTENCY IN TIMING, THOUGH SEEMS BETTER THAN THIS TIME  
YESTERDAY. AS SUCH, CONFIDENCE IN RESULTANT TEMPERATURES HAS GROWN  
SLIGHTLY, THOUGH STILL MODERATE AT BEST. THIS IS IN LARGE PART TO A  
VERY STRONG TEMPERATURE GRADIENT ACROSS THE FRONT, WHICH WILL RESULT  
IN LARGE TEMPERATURE CHANGES OVER SHORT DISTANCES, AS WELL AS RAPID  
DROPS IN TEMPERATURES OVER THE COURSE OVER A SHORT PERIOD OF TIME.  
HOURLY TEMPERATURE GRADIENT WILL LIKELY BE SHARPER THAN WHAT NBM  
CURRENTLY DEPICTS, BUT GIVEN THE AFOREMENTIONED UNCERTAINTY, DID NOT  
MAKE ANY SIGNIFICANT ADJUSTMENTS TO NBM TEMPS FOR TUESDAY.  
 
GIVEN INCREASED CONSENSUS IN TIMING, CONFIDENCE IN POST-FRONTAL  
PRECIP HAS LIKEWISE INCREASED, THOUGH STILL MODERATE AT 40-50%. WITH  
PRECIPITATION EXPECTED TO BE LARGELY POST-FRONTAL, P-TYPE WILL MOST  
LIKELY BE LIGHT SNOW, AND ALTHOUGH AMOUNTS ARE EXPECTED TO BE ON THE  
LIGHT SIDE (AROUND AN INCH OR LESS TUESDAY AFTERNOON), STRONG/GUSTY  
POST-FRONTAL WINDS OF 30-40+ MPH COULD CREATE AREAS OF BLOWING SNOW,  
ESPECIALLY WHILE THE SNOW IS FALLING.  
 
THIS COOL (NEAR TO BELOW NORMAL) AIR MASS DOES NOT LINGER TOO LONG,  
THOUGH IT WILL BRING SUB-ZERO WIND CHILLS TUESDAY NIGHT-WEDNESDAY  
MORNING, WITH HIGHS ONLY IN THE 20S FOR MANY AREAS ON WEDNESDAY.  
MOISTURE IS SPARSE BY WEDNESDAY, SO WOULD NOT EXPECT ANY LINGERING  
FLURRIES DESPITE THE COOLER TEMPERATURES ALOFT.  
 
THURSDAY-SATURDAY: WARMER AIR IS QUICK TO RETURN FOR THE LATTER PART  
OF THE WEEK, THOUGH READINGS ON THURSDAY COULD BE SLIGHTLY TEMPERED  
BY LINGERING SNOW COVER. THAT SAID, LOW LEVEL TEMPS SUPPORT TEMPS  
CLIMBING BACK INTO THE 50S ACROSS THE SOUTHWEST HALF OF THE FORECAST  
AREA THURSDAY, WITH HIGHS INTO THE 60S LIKELY RETURNING BY FRIDAY  
AND SATURDAY IN SOME AREAS.  
 

 
   
AVIATION /06Z TAFS THROUGH 06Z MONDAY/
 
 
ISSUED AT 1029 PM CST SAT FEB 24 2024  
 
VFR CONDITIONS PREVAIL THROUGH SUNDAY NIGHT, WITH MID AND HIGH  
CLOUDS. MAIN AVIATION CONCERN WILL BE THE WIND SHIFTS. LIGHT AND  
SOMEWHAT VARIABLE WINDS OVERNIGHT GIVE WAY TO WEST/NORTHWEST  
WINDS BY MID MORNING SUNDAY. EXPECT A SHIFT SOUTHERLY DURING THE  
EVENING HOURS. GUSTS AROUND 15 TO 20 KNOTS ARE POSSIBLE DURING  
THE LATE AFTERNOON AND EARLY EVENING HOURS, BUT EXPECT THEM TO  
DIMINISH QUICKLY AFTER SUNSET.  
 

 
   
FIRE WEATHER
 
 
ISSUED AT 233 PM CST SAT FEB 24 2024  
 
WELL-ABOVE NORMAL TEMPERATURES ON MONDAY WILL LEAD TO LOW-MODERATE  
AFTERNOON HUMIDITY LEVELS, VARYING FROM AROUND 20 PERCENT THROUGH  
PORTIONS OF THE MISSOURI RIVER VALLEY, TO 30-35 PERCENT NORTH OF THE  
I-90 CORRIDOR. THIS COMBINED WITH BREEZY SOUTHWEST-WEST WINDS WILL  
RESULT IN HIGH TO VERY HIGH GRASSLAND FIRE DANGER OVER MUCH OF THE  
FORECAST AREA, WITH THE EXCEPTION IN OUR FAR NORTHWEST AROUND HURON  
AND DE SMET, WHERE LIGHTER WINDS AND SLIGHTLY MORE MOIST/COOL SOIL  
CONDITIONS SHOULD LIMIT THE FIRE DANGER TO THE MODERATE CATEGORY ON  
MONDAY. AT THIS TIME, IT LOOKS LIKE WIND SPEEDS WILL BE MARGINAL FOR  
RED FLAG CONDITIONS IN OUR AREAS OF LOWEST HUMIDITY, BUT THIS WILL  
NEED TO BE MONITORED IN AREAS NEAR THE MISSOURI RIVER VALLEY  
MONDAY AFTERNOON.  
 
VERY STRONG NORTHERLY WINDS WILL DEVELOP BEHIND A COLD FRONT ON  
TUESDAY, BUT THINK FIRE DANGER WILL BE LIMITED BY DAYTIME TEMPS  
COLLAPSING INTO THE 30S AND EVEN 20S IN SOME AREAS.  
 

 
   
FSD WATCHES/WARNINGS/ADVISORIES
 
 
SD...NONE.  
MN...NONE.  
IA...NONE.  
NE...NONE.  
 

 
 

 
 
DISCUSSION...JH  
AVIATION...SG  
FIRE WEATHER...JH  
 
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