622   
FXUS63 KARX 041143  
AFDARX  
  
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
543 AM CST TUE NOV 4 2025  
   
KEY MESSAGES  
  
- WARM WEATHER CONTINUES FOR TODAY WITH HIGHS AROUND 60,  
  SLIGHTLY COOLER FOR THE LATTER PART OF THE WEEK, THEN MUCH  
  COLDER BY EARLY NEXT WEEK--HIGHS IN THE 30S AND LOWS IN THE  
  TEENS SUNDAY AND MONDAY.  
  
- BREEZY WEDNESDAY MORNING AND AGAIN THURSDAY WITH GUSTS UP TO  
  30-35 MPH. OTHERWISE DRY WEATHER UNTIL THURSDAY EVENING.  
  
- THE POTENTIAL FOR ACCUMULATING SNOW REMAINS ON THE TABLE FOR  
  SATURDAY AND SATURDAY NIGHT, THOUGH CONFIDENCE REMAINS LOW ON  
  THE SPECIFICS WITH AMOUNTS OR THE EXACT LOCATION OF THE SNOW  
  BAND.  
  
  
   
DISCUSSION  
  
ISSUED AT 305 AM CST TUE NOV 4 2025  
  
TODAY: WARM AND DRY  
  
SURFACE RIDGING CURRENTLY TRANSITING THE DRIFTLESS REGION   
PROGRESSES EASTWARD THIS MORNING WITH INCREASING SOUTHERLY FLOW   
TODAY. WEAK WARM AIR ADVECTION IN THE LOWER TROPOSPHERE (3 C   
INCREASE IN 850-MB TEMPS OVER 24 HOURS) NUDGES TEMPERATURES A   
FEW DEGREES WARMER COMPARED TO YESTERDAY WITH MANY LOCALES   
TOUCHING 60 DEGREES. A RIBBON OF 700-MB THETA-E ADVECTION MAY BE  
ABLE TO SATURATE ENOUGH TO PRODUCE LIGHT SPRINKLES NORTHEAST OF  
I-94 THIS EVENING, BUT OTHERWISE THE FORECAST FOR TODAY IS DRY.  
  
WED & THU: BREEZY PERIODS, SEASONAL TEMPERATURES, DRY  
  
A ZONAL PATTERN BRINGS THE NEXT VORT LOBE ACROSS THE ROCKIES   
TONIGHT, WHICH AMPLIFIES WEDNESDAY MORNING AS IT TRACKS ALONG   
THE U.S./CANADIAN BORDER AND THEN INTO THE GREAT LAKES IN THE   
AFTERNOON. A LEE TROUGH ACROSS THE NORTHERN HIGH PLAINS SHIFTS   
TO THE MID-MISSOURI RIVER VALLEY THIS EVENING WITH THE LOW   
CENTER CONTRACTING AS IT ALSO MOVES INTO THE GREAT LAKES EARLY   
WEDNESDAY MORNING. THE ISALLOBARIC WIND INCREASES AS UPSTREAM   
HIGH PRESSURE RAPIDLY BUILDS IN THE WAKE OF THE CYCLONE WITH THE  
ASSOCIATED PRESSURE GRADIENT TIGHTENING FROM 20 UBAR/KM TO   
NEARLY 40 UBAR/KM IN 12-18 HOURS.   
  
LOWER TROPOSPHERIC COLD AIR ADVECTION IN THE WAKE OF THE   
ATTENDANT COLD FRONT WILL AID TO FUNNEL THESE STRONGER WINDS TO   
THE SURFACE FOR A 6-9 HOUR PERIOD IN THE MORNING BEFORE THE   
PRESSURE GRADIENT RELAXES IN THE AFTERNOON. THE 04.00Z HREF 35   
MPH WIND GUST PROBABILITIES TOP OUT AROUND 80-90 PERCENT BETWEEN  
09-15Z (FOCUSED ON SOUTHEAST MINNESOTA INTO NORTHEAST IOWA AND   
SOUTHWEST WISCONSIN), TAPERING OFF QUICKLY THEREAFTER. HIGHER   
WIND GUST PROBABILITIES FALL OFF QUICKLY ABOVE THE 35 MPH   
THRESHOLD, WITH VALUES OF 30-50% FOR 40 MPH GUSTS AND <10% FOR   
45 MPH GUSTS.  
  
THE PROGRESSIVE PATTERN BRINGS HIGH PRESSURE THROUGH WEDNESDAY   
NIGHT WITH CYCLONIC FLOW AMPLIFYING FOR THURSDAY AND THE END OF  
THE WEEK. GUSTY SOUTHERLY WINDS ARE EXPECTED FOR THURSDAY   
DURING THE DAY AHEAD OF THE NEXT CYCLONE APPROACHING FROM THE   
DAKOTAS. THIS LOW AND THE BULK OF THE FORCING PASSES TO THE   
NORTH THURSDAY NIGHT, WITH ANY PRECIPITATION THAT MANAGES TO   
FORM ALONG THE TRAILING COLD FRONT BEING LIGHT IN NATURE. ONLY   
ABOUT 50% OF THE LREF MEMBERS DEVELOP ANY MEASURABLE   
PRECIPITATION OVER THE AREA, MAINLY EAST OF THE MISSISSIPPI   
RIVER, WITH ONLY A 10-20% CHANCE THAT RAINFALL AMOUNTS EXCEED   
0.10".  
  
COOLER AND MORE ACTIVE TO END THE WEEK  
  
A SECONDARY COLD FRONT BLASTS THROUGH THE REGION ON FRIDAY,   
SENDING TEMPERATURES FALLING THROUGH THE AFTERNOON/EVENING AND   
SETTING THE STAGE FOR A COLDER WEEKEND AND START TO NEXT WEEK.   
THERE EXIST A 10-15 DEGREE INTERQUARTILE SPREAD FOR HIGH   
TEMPERATURES ON FRIDAY (MID-40S TO MID-50S), INDICATIVE OF THE   
TIMING DISCREPANCIES IN WHEN THIS FRONT SLIDES THROUGH.  
  
A PV LOBE BREAKS OFF A NEGATIVELY-TILED TROUGH LIFTING UP ALONG  
THE PACIFIC NW COAST FRIDAY NIGHT, RACING ESE AND REACHING THE   
REGION SATURDAY INTO SATURDAY NIGHT. ACCOMPANIED BY FAVORABLE   
KINEMATIC FORCING, THE SYSTEM HAS THE POTENTIAL TO PRODUCE THE   
FIRST MEASURABLE SNOW FOR THE REGION. QUESTIONS STILL LINGER AS   
TO WHETHER THE THERMAL PROFILES WILL SUPPORT SNOW AND THE   
PLACEMENT OF THE ACCOMPANYING MESOSCALE FRONTOGENESIS FORCING.  
  
GIVEN THE FAST TRANSLATIONAL MOTION OF THE WAVE AND THE RAPID   
SURFACE CYCLONE DEVELOPMENT FRIDAY NIGHT/SATURDAY MORNING, IT IS  
UNDERSTANDABLE THAT THE MEDIUM RANGE ENSEMBLES STILL DIFFER   
SUBSTANTIALLY WITH SNOW AMOUNTS AND PLACEMENT. IT IS WORTH   
NOTING THAT THE DETERMINISTIC EC/GFS SOLUTIONS ARE SETTLING DOWN  
ON A SNOWFALL BAND SETTING UP IN SOUTHERN MINNESOTA/NORTHERN   
IOWA AND THEN SPREADING EAST INTO SOUTHERN WISCONSIN/NORTHERN   
ILLINOIS, AND HOPEFULLY THE ENSEMBLE MEMBERS REFLECT THIS TREND   
SOON.  
  
THE TIMING OF THIS SYSTEM ON SATURDAY MORNING PLAYS A KEY ROLE   
IN THE AMOUNT OF SNOW THAT FALLS DURING THE DAY. MEMBERS THAT   
BRING IN SNOW EARLIER IN THE MORNING AND LIMIT THE DEGREE OF   
DAYTIME HEATING BRING NOTABLY MORE SNOWFALL COMPARED TO THOSE   
THAT ARRIVE LATER IN THE MORNING OR MIDDAY. WHETHER SNOW RATES   
CAN OVERCOME WARMER GROUND TEMPERATURES (2 INCH TEMPS STILL IN   
THE MID-40S) IS ANOTHER QUESTION THAT REMAINS UNANSWERED. FOR   
NOW, WHILE CONFIDENCE IS INCREASING THAT THERE WILL BE SNOW IN   
THE REGION, THE PREDICTABILITY OF THE FORECAST REMAINS LOW. THE   
EC EXTREME FORECAST INDEX SUMS THIS CONCEPT WELL--DEPICTING A   
SHIFT OF TAILS CORRIDOR THROUGH THE REGION WITH THE ACTUAL EFI   
VALUES OF LESS THAN 50%.   
  
OF MUCH HIGHER CONFIDENCE (>95%) IS THE COLD SNAP LURKING FOR   
THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK AS POLAR AIR  
SURGES SOUTHWARD IN THE WAKE OF OUR SATURDAY SYSTEM. HIGH   
TEMPERATURES SHOULD STAY CONFINED IN THE 30S WITH LOWS IN THE   
20S TO EVEN TEENS MONDAY MORNING.  
  
  
   
AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/  
  
ISSUED AT 542 AM CST TUE NOV 4 2025  
  
LIGHT SOUTHERLY WINDS INCREASE LATER THIS MORNING WITH GUSTS  
APPROACHING 20 TO 25 MPH WEST OF THE MISSISSIPPI RIVER. THESE  
WINDS DIMINISH LATER THIS AFTERNOON THEN GRADUALLY TURN  
SOUTHWEST THIS EVENING AHEAD OF A WEAK COLD FRONT. THE   
NORTHWEST WIND SHIFT IS EXPECTED BETWEEN 08Z AND 11Z ACROSS THE   
REGION. WITH THIS WIND SHIFT, SUSTAINED WINDS OF 10 TO 20 MPH   
WITH GUSTS OF 20 TO 25 MPH EXPECTED FOR MUCH OF THE REGION WITH   
SOME AREAS WEST OF THE MISSISSIPPI RIVER APPROACHING 30 MPH FOR   
GUSTS AS WE HEAD TOWARDS THE END OF THE TAF PERIOD. VFR   
CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD AS THERE WILL BE  
SOME MID LEVEL CLOUDS BETWEEN 15KFT AND 20KFT FOR MUCH OF THE   
DAY.   
  
  
   
ARX WATCHES/WARNINGS/ADVISORIES  
  
WI...NONE.  
MN...NONE.  
IA...NONE.  
  
  
  
  
  
DISCUSSION...SKOW  
AVIATION...CECAVA  
 
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