260  
FXUS63 KARX 030009  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
609 PM CST SAT MAR 2 2024  
   
KEY MESSAGES
 
 
- RECORD WARMTH REMAINS IN STORE FOR SUNDAY AS TEMPERATURES PUSH  
INTO THE UPPER 60S TO LOW 70S. NEAR CRITICAL FIRE DANGER  
LEVELS DEVELOP IN THE AFTERNOON OVER PARTS OF NORTHEAST IOWA  
DUE TO STRONG WINDS AND LOWER HUMIDITY VALUES.  
 
- CONFIDENCE IS LOW ON ANY RAIN SHOWERS FOR SUNDAY WITH A BETTER  
SHOT OF RAIN ON MONDAY IN NORTHEAST IOWA AND WISCONSIN AS A  
FRONT STALLS OVER THE REGION.  
 
- WELL ABOVE AVERAGE TEMPERATURES IN THE UPPER 40S TO LOW 50S  
FOR HIGHS ON THE DOCKET FOR THIS WEEK. NEXT WIDESPREAD CHANCE  
OF PRECIPITATION COMES LATE IN THE WEEK.  
 

 
   
DISCUSSION
 
 
ISSUED AT 230 PM CST SAT MAR 2 2024  
 
SUNDAY: RECORD WARMTH, ISOLATED SHOWERS NORTH OF I-90  
 
BROAD SOUTHWESTERLY FLOW WAS IN PLACE ACROSS THE NORTH-CENTRAL  
U.S. THIS AFTERNOON WITH A BROAD THERMAL RIDGE ARCHING TO THE  
NNE FROM THE CENTRAL AND SOUTHERN HIGH PLAINS. DESPITE PERIODS  
OF HIGH CLOUDS STREAMING OVER THE UPPER LEVEL RIDGE AXIS, HIGHS  
SURGED INTO THE UPPER 50S TO LOW 60S GIVEN THE TEMPERATURES OF  
+9 TO +11 C AT THE TOP OF THE BOUNDARY LAYER. A STRONG  
NEGATIVELY-TILTED SHORTWAVE EJECTS FROM THE BASE OF QUASI-  
STATIONARY PACIFIC NW LONGWAVE TROUGH TONIGHT AND INTO THE DAY  
ON SUNDAY. WARM AIR/POSITIVE THETA-E ADVECTION ENSUES AHEAD OF  
THIS SHORTWAVE WITH SOUTHERLY WINDS LIKEWISE INCREASING TONIGHT  
AND SUNDAY MORNING AS A LEE TROUGH EJECTS FROM THE FRONT RANGE.  
OVER 90 PERCENT OF THE EPS GUIDANCE HAS HIGHS EXCEEDING RECORD  
VALUES FOR SUNDAY AHEAD OF THIS FRONT AND HAVE CONTINUED TO PUSH  
THE FORECAST WELL ABOVE THE DETERMINISTIC NBM GUIDANCE FOR  
HIGHS.  
 
THE BIGGEST WILD CARDS IN TOMORROW'S FORECAST REVOLVE AROUND  
ANY LOW STRATUS IN THE MORNING AND THE STRENGTH OF THE ELEVATED  
MIXED LAYER (EML) IN THE AFTERNOON. A FEW, BUT INCREASING  
NUMBER, OF THE 12Z HREF MEMBERS BRING LOW STRATUS IN BY SUNRISE  
AS LOW-LEVEL MOISTURE INCREASES AT THE TOP OF THE BOUNDARY  
LAYER. THESE CLOUDS SHOULD BURN OFF QUICKLY BY LATE MORNING, BUT  
COULD SHAVE AN HOUR OR TWO OFF OUR MIXING PERIOD AND KNOCK A  
COUPLE OF DEGREES OFF THE HIGHS. AS THE NEGATIVELY-TILTED WAVE  
APPROACHES AND A SURFACE BOUNDARY SLIDES IN FROM THE WEST,  
FORCING FOR ASCENT WILL BE QUITE STRONG BUT MOISTURE SERIOUSLY  
LACKING. HAVE LEANED THE POP FORECAST MORE INTO THE CAM REALM  
FOR THE DEWPOINT AND EML CHARACTERISTICS JUST AHEAD OF THIS  
FRONT, WHICH SHUNT ALL OF THE PRECIPITATION NORTH OF INTERSTATE  
94. THIS IS A MODEST SHIFT IN THE FORECAST AND A FAIR NUMBER OF  
GLOBAL MODELS (30-40%) STILL HAVE PRECIP ALONG AND EAST OF THE  
MISSISSIPPI RIVER. HOWEVER, GIVEN THE HIGH LIKELIHOOD THAT WE  
WILL OVERACHIEVE TEMPERATURE-WISE AND THE 15-20C DEWPOINT  
DEPRESSIONS IN THE BL IN THE RAP/HRRR FORECAST PROFILES, THE  
ODDS ARE BETTER THAN NOT THAT THE ATMOSPHERE WILL SIMPLY BE TOO  
DRY TO SUPPORT PRECIPITATION SOUTH OF CENTRAL WISCONSIN.  
 
MONDAY: SHOWERS LIKELY, MAINLY IN NE IOWA AND WI  
 
THE AFOREMENTIONED SURFACE BOUNDARY SLIDES THROUGH THE FORECAST  
AREA SUNDAY NIGHT, BUT STALLS ALONG A SW TO NE LINE FROM  
ROUGHLY DES MOINES TO MADISON WITH THE LOWER TROPOSPHERIC FRONT  
SLANTED FURTHER TO THE NORTHWEST ACROSS MUCH OF THE FORECAST  
AREA. THIS IS IN RESPONSE TO THE UPPER WAVE LIFTING TO THE NORTH  
AND ITS ENERGY BEING PARTIALLY REABSORBED BY THE NOW ADVANCING  
TROUGH TRACKING IN FROM THE PACIFIC NW. AS THIS SECOND TROUGH  
ARRIVES AND THE THERMAL PROFILES COOL ALONG THE FRONT, THE  
ATMOSPHERE WILL BE MORE SUPPORTIVE OF SHOWERS ALONG THIS FRONTAL  
SURFACE. OVERALL RAINFALL AMOUNTS LOOK TO BE LIGHT (<0.25"),  
THOUGH ABOUT 20% OF THE GUIDANCE HAS GREATER THAN 0.50" OF  
RAINFALL GIVEN THAT THERE IS SOME UPRIGHT INSTABILITY IN PLAY  
THAT COULD RESULT IN LOCALLY HIGHER RAINFALL AMOUNTS. THIS  
PRECIP SHIFTS OUT OF THE REGION MONDAY EVENING WITH THE  
DEPARTING TROUGH.  
 
TUESDAY - SATURDAY: WARM, NEXT ROUND OF PRECIP LATE WEEK  
 
TEMPERATURES "COOL" BACK INTO THE LOWER 50S FOR HIGHS TO START  
THE WEEK AND SLOWLY FALL BACK INTO THE UPPER 40S FOR HIGHS  
(LOWER 30S FOR LOWS) BY THE END OF THE WEEK GIVEN THAT THE  
LOWER TROPOSPHERIC FLOW HAS A NORTHERLY OR EASTERLY COMPONENT  
DURING THIS PERIOD. THIS IS STILL 10+ DEGREES ABOVE NORMAL FOR  
THIS TIME OF YEAR.  
 
THE NEXT ROUND OF PRECIPITATION ARRIVES FOR THE LATTER PART OF  
THE WEEK AS A DEEPER LONGWAVE TROUGH DIGS ACROSS THE WESTERN  
CONUS, THOUGH PLENTY OF VARIABILITY CREEPS INTO THE FORECAST FOR  
THIS SYSTEM AND MAKES IT DIFFICULT TO PIN DOWN MUCH FOR  
SPECIFICS. MORE THAN HALF OF THE LONGER RANGE SOLUTIONS HAVE  
OVER 0.10" OF LIQUID PRECIPITATION AND 20-30% HAVE OVER 0.50" OF  
LIQUID PRECIPITATION. SUFFICE TO SAY, THIS MAY BE OUR NEXT  
DECENT SHOT OF RAINFALL. ONE CANNOT FULLY RULE OUT THAT SOME OF  
THIS PRECIPITATION FALLS OUT AS SNOW GIVEN THE COOLER PROFILES  
PROGGED. WHILE SUCH DETAILS ARE MURKY, AT THE PRESENT TIME  
ABOUT 40-50% OF THE LONGER RANGE GUIDANCE SUPPORTS MEASURABLE  
SNOW AND 20-30% HAVE OVER AN INCH OF SNOW. THESE NUMBERS HAVE  
BEEN ON THE INCREASE OVER THE LAST 24 HOURS OF MODEL RUNS.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z MONDAY/
 
 
ISSUED AT 609 PM CST SAT MAR 2 2024  
 
VFR CONDITIONS REMAIN FOR THE START OF THE TAF PERIOD. MAIN  
CONCERNS WILL REVOLVE AROUND WINDS, BUT GUIDANCE WOULD CONTINUE  
TO HIGHLIGHT THE POTENTIAL FOR A SHORT PERIOD OF LOWER CEILINGS  
(MVFR) SUNDAY MORNING AS A SURFACE FRONT MOVES THROUGH THE  
AREA. THERE IS SOME VARIABILITY AMONG GUIDANCE SO HAVE  
MAINTAINED THE PREVIOUS SCT-BKN MENTION, BUT WILL CONTINUE TO  
MONITOR TRENDS. SOUTH WINDS WILL CONTINUE TO INCREASE WITH WINDS  
GUSTING TO AROUND 25 TO 35 KTS ON SUNDAY. THERE IS SOME  
CHALLENGE WITH WINDS FOR OVERNIGHT TONIGHT WITH SOME QUESTION ON  
WHETHER KLSE WILL DECOUPLE. IF SO, UPDATES MAY BE NEEDED TO  
WINDS AND THE MENTION OF LLWS WOULD NEED TO BE ADDED. WILL BE  
CLOSELY MONITORING OBSERVATIONS AND TRENDS IN GUIDANCE.  
 

 
   
FIRE WEATHER
 
 
ISSUED AT 230 PM CST SAT MAR 2 2024  
 
IT STILL LOOKS LIKE THERE WILL BE ELEVATED TO NEAR-CRITICAL FIRE  
WEATHER CONDITIONS POSSIBLE SUNDAY. THIS IS DUE A COMBINATION OF  
RECORD WARM TEMPERATURES, DRY RELATIVE HUMIDITIES, AND STRONG  
SOUTHERLY WINDS. HIGH TEMPERATURES BE IN THE 60S NORTH OF INTERSTATE  
94 AND IN THE LOWER TO MID-70S ELSEWHERE. LOWERED AFTERNOON DEW  
POINTS CLOSE TO THE NBM 10TH PERCENTILE. THIS RESULTED IN AFTERNOON  
HUMIDITIES WEST OF THE MISSISSIPPI RIVER FALLING INTO THE 25 TO 40  
PERCENT WEST OF MISSISSIPPI RIVER AND FROM 25 TO 50 PERCENT IN  
WESTERN WISCONSIN. A STRENGTHENING SOUTHERLY WINDS AHEAD OF AN  
APPROACHING COLD FRONT WILL RANGE FROM 20 TO 35 MPH AND WIND GUSTS  
FROM 30 TO 40 MPH. THE GFDI CLIMBS UP INTO EXTREME RANGE ACROSS  
SOUTHERN PORTIONS OF FAYETTE AND CLAYTON COUNTIES.  
 

 
   
CLIMATE
 
 
ISSUED AT 230 PM CST SAT MAR 2 2024  
 
WITH NAEFS 850 MB TEMPERATURES ANOMALIES OF 2 TO 2.5 STANDARD  
DEVIATIONS ON SUNDAY, WE ARE LOOKING AT RECORD HIGH TEMPERATURES ON  
SUNDAY. UNLIKE EARLIER IN THE WEEK WHERE TEMPERATURES COOLED RAPIDLY  
OVERNIGHT, IT MIGHT BE WARM ENOUGH ON SUNDAY MORNING THAT SOME WARM  
LOW RECORDS COULD BE TIED OR BROKEN. WHETHER ANY WARM LOW  
TEMPERATURE RECORDS ARE TIED OF BROKEN WILL BE HIGHLY DEPENDENT UPON  
THE SUNDAY/MONDAY MIDNIGHT TEMPERATURE.  
 
ROCHESTER MN FORECAST RECORD/YEAR  
 
SUN MAR 3 70 56/1946  
 
LA CROSSE WI FORECAST RECORD/YEAR  
 
SUN MAR 3 72 66/1894  
 

 
   
ARX WATCHES/WARNINGS/ADVISORIES
 
 
WI...NONE.  
MN...NONE.  
IA...NONE.  
 

 
 

 
 
DISCUSSION...SKOW  
AVIATION...EMS  
FIRE WEATHER...BOYNE  
CLIMATE...BOYNE  
 
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