749  
FXUS63 KABR 121536 AAB  
AFDABR  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE ABERDEEN SD  
1036 AM CDT WED MAR 12 2025  
   
KEY MESSAGES
 
 
- INCREASING SOUTH TO SOUTHWEST WINDS, WITH GUSTS OF 20 TO 30 MPH,  
RELATIVE HUMIDITY DROPPING AT OR BELOW 20%, AND ONGOING DRY FUELS  
HAS LED TO THE ISSUANCE OF A FIRE WEATHER WATCH FOR SOUTH CENTRAL SD  
THURSDAY AFTERNOON AND EVENING.  
 
- CHANCES FOR PRECIPITATION REMAIN POSSIBLE LATE IN THE WEEK AS A  
STORM SYSTEM MOVES THROUGH THE REGION. RAIN, A RAIN/SNOW/LIGHT  
FREEZING RAIN MIX OR JUST SNOW IN NORTH WINDS WILL BE POSSIBLE FOR  
PARTS OF THE AREA FRIDAY NIGHT THROUGH SATURDAY.  
 

 
   
UPDATE
 
 
ISSUED AT 1031 AM CDT WED MAR 12 2025  
 
NO APPRECIABLE CHANGES ARE EXPECTED FOR THE REMAINDER OF TODAY'S  
FORECAST. A MIX OF SUN AND HIGH CLOUDS AND LIGHT WINDS ARE STILL  
ANTICIPATED THROUGH THE AFTERNOON. AFTERNOON READINGS WILL TOP OUT  
IN THE 50S TO LOW 60S IN THE EAST TO THE LOW TO MID 60S ACROSS  
CENTRAL SOUTH DAKOTA.  
 
UPDATE ISSUED AT 613 AM CDT WED MAR 12 2025  
 
SEE BELOW FOR AN AVIATION FORECAST DISCUSSION FOR THE 12Z TAFS.  
 

 
   
SHORT TERM /TODAY THROUGH THURSDAY AFTERNOON/
 
 
ISSUED AT 353 AM CDT WED MAR 12 2025  
 
MAIN CONCERN IN THE SHORT TERM WILL BE THE RETURN OF ELEVATED FIRE  
DANGER ON THURSDAY. OTHERWISE, ENSEMBLES AGREE ON ZONAL FLOW ALOFT  
AND A NEGATIVE TILTED RIDGE TO OUR WEST TODAY. THIS RIDGE WILL SHIFT  
EASTWARD, WITH THE CREST OF THE RIDGE FROM NORTHERN  
ALBERTA/SASKATCHEWAN AND SOUTHEASTWARD THROUGH THE NORTHERN PLAINS  
BY THURSDAY AFTERNOON, WHICH WILL SWITCH WINDS OUT OF THE SOUTHWEST.  
BEHIND THE RIDGE, A DEEP TROUGH MOVES IN OVER THE WESTERN CONUS  
THURSDAY, WITH A SHORTWAVE SETTING UP OVER SOUTHERN ALBERTA ON THE  
NORTHERN STREAM OF THIS WAVE BY THURSDAY EVENING. WEAK SURFACE  
RIDGING TODAY KEEPS THE AREA DRY WITH A WARM FRONT, BECOMING  
STATIONARY, SETTING UP OVER WESTERN TO SOUTHERN SD THIS EVENING  
THROUGH THURSDAY MORNING. THE LOW, ASSOCIATED WITH THIS SHORTWAVE,  
WILL MOVE IN OVER NORTHERN MT ~THURSDAY AFTERNOON/EVENING, WITH A  
DRYLINE SETTING UP VERTICALLY ALONG THE LEE SIDE OF THE ROCKIES FROM  
THE CENTER OF THE LOW. THIS LEAVES THE CWA IN THE WARM SECTOR WITH  
SOUTH/SOUTHWEST WINDS AT THE SURFACE.  
 
WARMER AIR MOVES IN TODAY WITH THE RIDGE AS HREF'S 925MB-850MB TEMPS  
THIS AFTERNOON RANGE FROM +6 TO +14C, WARMEST OVER CENTRAL AND SOUTH  
CENTRAL SD. MIXING LEVELS ARE PRETTY SHALLOW, PER RAP SOUNDINGS,  
WITH THE TOP OF THE MIXED LAYER UP TO 800-850MB. FORECASTED HIGHS  
FOR TODAY WILL BE WARMER THAN YESTERDAY RANGING IN THE UPPER 50S TO  
THE MID 60S. SOUTH TO SOUTHEASTERLY WINDS TONIGHT WILL KEEP IT  
WARMER THAN LAST NIGHT WITH LOWS RANGING IN THE LOWER TO UPPER 30S.  
BY THURSDAY AFTERNOON, AND BEING IN THE WARM SECTOR SIDE OF THE LOW  
WITH SOUTH TO SOUTHWEST WINDS AS MENTIONED (AND RIDGE ALOFT), 925  
TEMPS WILL RANGE FROM +17 TO +21C WHICH MAX IS 17.1C AND DAILY MAX  
IS 18.6C, PER ABR SOUNDING CLIMATOLOGY! MIXING LEVELS ARE  
HIGHER/DECENT MIXING, HOWEVER, MID TO HIGH CLOUDS ARE IN THE  
FORECAST DURING THIS TIME AND "MAY" LIMIT SOME OF THE STRONGEST  
MIXING IN THE AFTERNOON OR IF THEY END UP BEING THICKER THAN  
GUIDANCE. I WENT AHEAD AND KEPT TEMPS ABOVE GUIDANCE WITH HIGHS  
FORECASTED WELL INTO THE UPPER 60S TO UPPER 70S, WARMEST OVER SOUTH  
CENTRAL SD. THIS IS AN IMPRESSIVE 30 TO 35 DEGREES ABOVE AVERAGE.  
ALSO, WE COULD BREAK RECORDS FOR HIGH TEMPS AT KABR, KATY (OR TIE),  
AND K8D3. EC EFI RANGES FROM 0.7-0.9 FOR TMAX OVER THE CWA WITH A  
SHIFT OF TAILS OF ZERO EAST OF THE MISSOURI RIVER TO ABOUT THE JAMES  
RIVER, HELPING TO INCREASE CONFIDENCE.  
 
WITH THE LOW TO OUR WEST/NORTHWEST ON THURSDAY, PRESSURE GRADIENTS  
WILL INCREASE A BIT. ALONG WITH DAYTIME HEATING/WAA, THIS WILL  
INCREASE OUR WINDS THROUGH THE AFTERNOON WITH SUSTAINED WINDS  
BETWEEN 10-20 MPH AND GUSTS OF 25-35 MPH. HIGHEST GUSTS WILL BE  
OVER AND DOWNSLOPE OF THE SISSETON HILLS AND OVER PORTIONS OF SOUTH  
CENTRAL SD. RH WILL ALSO TANK AT OR BELOW 20% FOR BROWN/SPINK  
COUNTIES AND WESTWARD AND 25-35% EASTWARD OF HERE. THE GRASSLAND  
FIRE DANGER INDEX IS VERY HIGH FOR MUCH OF THE CWA. SO WITH THE  
WINDS OVER SOUTH CENTRAL SD/LOW RH CRITERIA, I DID ISSUE A FIRE  
WEATHER WATCH FROM STANLEY THROUGH HAND COUNTIES AND SOUTHWARD FROM  
18Z THURSDAY TO 01Z FRIDAY.  
 

 
   
LONG TERM /THURSDAY EVENING THROUGH TUESDAY/
 
 
ISSUED AT 353 AM CDT WED MAR 12 2025  
 
WHEN THE PERIOD OPENS, A RETURN FLOW PRESSURE GRADIENT HAS SOUTHERLY  
WINDS ONGOING OVER THE CWA AND A RATHER WARM AIRMASS (850HPA TEMPS  
2+ STANDARD DEVIATIONS ABOVE NORMAL OFF THE NAEFS/ENS S.A. TABLE) IN  
PLACE.  
 
THE LEE-OF-THE ROCKIES SURFACE TROF SHIFTS OVER INTO THE DAKOTAS AND  
NEBRASKA (BECOMING AN INVERTED SURFACE TROF) ON FRIDAY AS AN UPPER  
LOW MAKES ITS MOVE OUT ONTO THE PLAINS. THE INVERTED SURFACE TROF  
BECOMES A REFLECTION OF UPPER LEVEL DEFORMATION ZONE DEVELOPMENT  
FRIDAY INTO FRIDAY NIGHT.  
 
COMPARED TO 24 HOURS AGO, OVERALL SYSTEM TIMING IS RELATIVELY  
UNCHANGED, BUT THE TRACK HAS TAKEN A JOG BACK TO THE WEST BY ~150  
MILES, GIVE OR TAKE, SHIFTING THE DEFORMATION ZONE PRECIPITATION  
THAT DEVELOPS FRIDAY EVENING INTO THE OVERNIGHT A LITTLE BIT FURTHER  
WEST OVER THE REGION. IF LIGHT PRECIPITATION DEVELOPS BACK TOWARD  
THE MISSOURI RIVER VALLEY ON FRIDAY, IT WOULD BE RAIN WHILE  
STRENGTHENING NORTHERLY WINDS ARE OCCURRING.  
 
PRECIPITATION THAT DEVELOPS OUT OVER EASTERN/SOUTHEASTERN SOUTH  
DAKOTA, NORTHWESTERN IOWA AND SOUTHWESTERN MINNESOTA FRIDAY  
AFTERNOON INTO FRIDAY EVENING LIKELY SETS THE NORTH/WESTERN EDGE OF  
DEFORMATION ZONE PRECIPITATION (RAINFALL). AS THE UPPER LOW MOVES  
NORTH-NORTHEAST THROUGH MINNESOTA LATE FRIDAY NIGHT THROUGH  
SATURDAY, THERE IS A PHASE CHANGE EXPECTED IN DEF-ZONE PRECIPITATION  
FROM RAIN TO SNOW, AND NORTH WINDS ARE EXPECTED TO BE EXPANDING OVER  
TO NEAR THE DAKOTAS BORDER WITH MINNESOTA SATURDAY MORNING. QPF  
CLUSTERS ANALYSIS HAS VERY LITTLE PRECIPITATION OCCURRING OVER THE  
CWA ON FRIDAY, PRIOR TO 00Z SATURDAY, BUT DOES STILL SHOW SOME  
ENSEMBLE-BASED QPF OVER THE FAR EASTERN ZONES FOR FRIDAY  
NIGHT/SATURDAY.  
 
P-TYPE DURING THE DAY ON FRIDAY WOULD BE RAIN, IF ANY IS ABLE TO  
DEVELOP AND REACH THE GROUND UNDER THESE DEVELOPING/STRENGTHENING  
(DRY) NORTH WINDS BEHIND THE INVERTED SURFACE TROF. THE PRIMARY  
TIMEFRAME OF CONCERN FOR HAZARDOUS WEATHER COMES GENERALLY AFTER  
MIDNIGHT (MIDDLE OF FRIDAY NIGHT) SATURDAY WHEN DEFORMATION ZONE  
(RAIN) PRECIPITATION SITTING OVER THE I-29 CORRIDOR OR PERHAPS  
BACKING WESTWARD A BIT TOWARD THE JAMES RIVER VALLEY CHANGES OVER TO  
SNOW AND BEGINS TO INTERACT WITH 25+MPH SUSTAINED WINDS AND HIGHER  
GUSTS FOR THE REST OF FRIDAY NIGHT AND ON INTO SATURDAY, WHERE-EVER  
DEF-ZONE PRECIPITATION PERSISTS. QPF GUIDANCE IS HIGHLIGHTING THE  
COUNTIES EAST OF BROWN/SPINK WITH SOME HEFTY QPF AMOUNTS IN EXCESS  
OF 0.50IN, BUT THAT'S NOT ALL FOR MAKING SNOW WITH. AGAIN, SOME OF  
THAT IS RAIN QPF AND THEN SOME OF IT IS SNOW QPF. RUNNING IT THROUGH  
THE FORECAST PROCESS ENDED UP YIELDING ABOUT 0.5IN-1.5IN OF SNOW IN  
THE JAMES RIVER VALLEY WITH HIGHER AMOUNTS FURTHER EAST. THE (NBM)  
PROBABILITY OF SEEING 3 OR MORE INCHES OF SNOW BETWEEN 7 PM CDT  
FRIDAY AND 7 PM CDT SATURDAY REMAINS GENERALLY AROUND 30 TO 60  
PERCENT ACROSS THE JAMES RIVER VALLEY OVER TO THE EASTERN CWA EDGE.  
 
SURFACE TEMPERATURES FORECAST WHILE IT'S SNOWING ARE FAIRLY WARM  
(MID 20S TO LOW 30S), AND SNOW RATIOS ARE RATHER LOW RIGHT NOW FOR  
THIS EVENT, RANGING ANYWHERE FROM 5:1 TO 12:1. SO, HEAVY/WET SNOW  
THAT COMPACTS QUICKLY AND IS LESS THAN IDEAL FOR BLOWING AROUND.  
BLOWING SNOW MODEL "SEES" THAT, AS IT BASICALLY REMOVES BLOWING SNOW  
POTENTIAL IF FALLING SNOW POTENTIAL IS REMOVED OR REDUCED TO A  
CERTAIN RATE/AMOUNT IN SO MANY HOURS. FROM LATE FRIDAY NIGHT THROUGH  
EARLY SATURDAY AFTERNOON, WHEN SNOW IS FALLING, THERE COULD BE  
OCCASIONAL/PERIODS OF SCATTERED WHITEOUT CONDITIONS UP ON THE COTEAU  
OVER INTO WEST CENTRAL MINNESOTA. BUT, ONCE THE FALLING SNOW  
COMPONENT IS REMOVED, THE PROBABILITY OF GREATLY REDUCED VISIBILITY  
GREATLY DROPS OFF (STILL SOME SURFACE-LEVEL BLOWING/DRIFTING SNOW  
POTENTIAL).  
 
BEYOND THIS SYSTEM, THERE IS A PERIOD OF DRY/STABLE CONDITIONS  
SUNDAY WHILE HIGH PRESSURE AT THE SURFACE/ALOFT MOVES OVER THE CWA.  
EARLY NEXT WEEK, THE UPPER FLOW PATTERN GOES NEARLY ZONAL BEFORE  
ANOTHER LONGWAVE TROF MOVES ACROSS THE NATION'S MID-SECTION. THERE  
ARE STILL SOME TIMING ISSUES SURROUNDING THIS LONGWAVE TROF. BUT,  
FOR NOW SOME 15 TO 30 PERCENT CHANCES FOR PRECIPITATION COVER THE  
TUESDAY FORECAST PERIOD. TEMPERATURES ON MONDAY COULD WARM UP TO  
MUCH ABOVE NORMAL. BUT, SUNDAY AND TUESDAY LOOK MORE LIKE 5 TO 15  
DEGREE ABOVE NORMAL DAYS, TEMP-WISE.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z THURSDAY/
 
 
ISSUED AT 613 AM CDT WED MAR 12 2025  
 
TERMINALS KABR,KATY,KPIR,KMBG  
 
VFR CONDITONS ARE EXPECTED THROUGH THE TAF PERIOD WITH JUST SOME  
SCATTERED/BROKEN HIGH CIRRUS CLOUDS AROUND TODAY/TONIGHT.  
 

 
   
ABR WATCHES/WARNINGS/ADVISORIES
 
 
SD...FIRE WEATHER WATCH FROM THURSDAY AFTERNOON THROUGH THURSDAY  
EVENING FOR SDZ033>037-045-048-051.  
 
MN...NONE.  

 
 

 
 
UPDATE...VIPOND  
SHORT TERM...MMM  
LONG TERM...DORN  
AVIATION...DORN  
 
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