619  
FXUS63 KARX 161111  
AFDARX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LA CROSSE WI  
611 AM CDT FRI MAY 16 2025  
   
KEY MESSAGES  
 
- WINDY TODAY WITH GUSTS FROM 35 TO 45 MPH. SCATTERED TO AREAS OF  
SHOWERS THROUGH TONIGHT.  
 
- DRIER, COOLER AND LESS WINDY END TO THE WEEKEND.  
 
- WIDESPREAD RAIN CHANCES RETURN FOR MONDAY INTO WEDNESDAY.  
 
 
   
DISCUSSION  
 
ISSUED AT 245 AM CDT FRI MAY 16 2025  
 
TODAY-TONIGHT: WINDY. SCATTERED TO AREAS OF SHOWERS.  
 
THE UPPER LEVEL CLOSED LOW IS EDGING INTO WESTERN MN EARLY THIS  
MORNING, SHIFTING OVER NORTHERN WI THIS EVENING. LOBES OF SHORTWAVE  
ENERGY WILL ROTAT.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... ISSUED  
AT 631 PM CDT THU MAY 15 2025  
 
STRONG SUBSIDENCE AND STEEP 1000-700 MB LAPSE RATES WILL CONTINUE TO  
MIX STRONG SOUTHWEST WINDS TO THE SURFACE. SUSTAINED WINDS WILL  
RANGE FROM 25 TO 35 KNOTS WITH GUSTS TO 50 KNOTS. THESE WINDS HAVE  
BEEN PICKING UP DUST FROM RECENTLY PLOWED FARM FIELDS AND LOWERING  
VISIBILITIES TO 2 MILES OR LESS AT TIMES.  
 
AS DIURNAL MIXING OCCURS ON FRIDAY, THE SUSTAINED SOUTHWEST WINDS  
WILL RANGE FROM 20 TO 30 KNOTS AND GUST FROM 30 TO 45 KNOTS DURING  
THE LATE MORNING AND AFTERNOON.E AROUND THE LOW WHILE SHORT TERM  
GUIDANCE ALSO FAVORS STREAKING A WEAK RIPPLE FROM THE SOUTHERN  
PLAINS TO ACROSS SOUTHERN WI BY THE AFTERNOON. ADD IN FAVORABLE LOW  
LEVEL LAPSE RATES AND AMPLE SATURATION AND SCATTERED TO AREAS OF  
SHOWERS WILL BE THE RESULT. THE INSTABILITY AXIS IS SHIFTING EAST SO  
NOT ANTICIPATING MUCH/IF ANY THUNDER THREAT.  
 
CURRENTLY ACROSS SD, JUST WEST OF THE SFC LOW CENTER, WINDS ARE  
GUSTING IN THE UPPER 30S/LOWER 40S MPH. THAT LOW SHIFTS OVER  
NORTHERN WI THIS EVENING, BUT IS PROGGED TO UNDERGO SOME WEAKENING  
AS IT DOES. LOW LEVEL WINDS BECOME UNIDIRECTIONAL ACROSS THE  
FORECAST AREA THIS MORNING, PROMOTING DEEP MIXING UPWARDS OF 9 KFT  
AT TIMES. RAP/HRRR SUGGEST WINDS AT THE TOP OF THE MIX LAYER COULD  
FLIRT WITH THE UPPER 50S/60 KTS, BUT ONLY BRIEFLY. GENERALLY, BOTH  
BRING UPPER 30S TO NEAR 40 KTS TO THE SFC VIA MOMENTUM TRANSFER,  
TOPPING GUSTS OUT IN THE LOWER 40S MPH. FLIRTING WITH WIND ADVISORY  
CRITERIA, BUT MOSTLY BELOW. HOWEVER, IF THE EC IS TO BE BELIEVED,  
THE WIND PRONE AREAS WEST OF THE MISSISSIPPI RIVER WILL BE GUSTING  
WELL INTO THE 50S MPH (ALMOST 10% OF ITS MEMBERS REACH 60 AT KRST).  
EFIS FOR WIND GUSTS CONTINUE 0.8 TO 0.9 TODAY WITH SOT OF 1. THE EPS  
HAS BEEN RUNNING "HOT" WHEN IT COMES TO WINDS AND DOESN'T HAVE A LOT  
OF SUPPORT FROM THE OTHER SHORT/MEDIUM RANGE GUIDANCE. THE GEFS, FOR  
INSTANCE, HAS ONLY 20% OF ITS MEMBERS REACHING 45 MPH AT KRST.  
LATEST HREF SUGGESTS APPROX 40-80% FOR 40 MPH GUSTS FOR MUCH OF THE  
FORECAST AREA, BUT ONLY SPOTTY 10-20% TO EXCEED 45.  
 
TOSSING A LOT OF NUMBERS, PERCENTAGES OUT THERE...PRESENTING A MUDDY  
PICTURE. SENSIBLE OUTCOMES SAY IT'S GOING TO BE WINDY EITHER WAY.  
FOR NOW, PER COORDINATION WITH SURROUNDING OFFICES, WILL HOLD  
OF AN ADVISORY. WILL KEEP A CLOSE EYE ON EVOLUTION/SFC  
OBSERVATIONS THROUGH THE DAY, ADJUSTING FORECAST AND POTENTIAL  
HEADLINE NEEDS IF WARRANTED.  
 
 
- WEEKEND: COOLER, LINGERING SHOWERS SATURDAY. SUNDAY DRY, SUNNY  
WITH MUCH LIGHTER WINDS.  
 
THE UPPER LEVEL CLOSED LOW WILL BE ACROSS MICH SAT MORNING, EXITING  
OVER THE EASTERN GREAT LAKES BY SAT EVENING. CYCLONIC FLOW,  
LINGERING BITS OF SHORTWAVE ENERGY, POTENTIALLY A WESTWARD HANGING  
SFC TROUGH ALONG WITH FAVORABLE LOW LEVEL LAPSE RATES WILL CONTINUE  
A SMATTERING OF SHOWERS SAT - MOSTLY ACROSS WI. THESE SHOULD ALL  
EXIT EAST BY THE EVENING. A SHORTWAVE RIDGE A LOFT MOVES IN FOR  
SUNDAY, BRINGING THE WEEKEND TO A DRY, LESS WINDY, MOSTLY SUNNY AND  
SEASONABLE CLOSE.  
 
- START OF NEW WORK WEEK: PERIODS OF SHOWERS  
 
GEFS AND EPS HAVE BEEN FAVORING BRINGING A LONGWAVE TROUGH FROM OFF  
THE WEST COAST THIS WEEKEND, MOVING IT OVER THE MID MISSISSIPPI  
RIVER VALLEY BY TUE MORNING. BITS OF SHORTWAVE ENERGY WILL PINWHEEL  
AROUND THE TROUGH. FAIRLY MESSY SETUP AS THERE WILL BE A FEW  
SHORTWAVES AT PLAY THAT COULD MERGE/STAY SOLO/OR COME TOGETHER WELL  
EAST OF THE LOCAL AREA. WHILE THESE DETAILS AREN'T CLEAR, A BRANCH  
OF THE LOW LEVEL JET LOOKS TO FUNNEL MOISTURE NORTH THEN WESTWARD,  
FEEDING THE UPPER LEVEL FORCING. SENSIBLE OUTCOMES, SANS CLARITY IN  
SOME OF THE FINER DETAILS, IS FOR AREAS OF RAIN TO SPREAD ACROSS THE  
FORECAST AREA AS EARLY AS MON MORNING, WITH PERIODS OF RAIN  
POTENTIALLY LINGERING INTO WED. THE EPS AND GEFS ARE A BIT QUICKER  
WITH BRINGING IN THE RAIN CHANCES COMPARED TO PREVIOUS RUNS AND  
THERE HAS BEEN SOME SHIFT SOUTHWARD IN THE GEFS. FOR NOW, WILL LET  
THE MODEL BLEND DETAIL THE RAIN CHANCES - WHICH ARE STILL LOOKING  
LIKELY FOR A LARGE PORTION OF THE FORECAST AREA. THE CURRENT TRACK  
OF THE TROUGH WOULD HOLD MUCH/IF NOT ALL OF THE INSTABILITY POOL  
WELL SOUTH, LIMITING THE THREAT FOR THUNDER.  
 
 
   
AVIATION /12Z TAFS THROUGH 12Z SATURDAY/  
 
ISSUED AT 543 AM CDT FRI MAY 16 2025  
 
MAIN FORECAST CONCERN WILL BE INCREASING WINDS THROUGH TODAY.  
HIGHER WINDS HAVEN'T PROGRESSED AS FAR EAST AS PREVIOUSLY  
FORECASTED AND AS A RESULT HAVE HAD TO AMEND KRST TAF SITE TO  
ACCOUNT. HOWEVER, HAVE CONTINUED MENTION OF INCREASED WINDS AT  
BOTH TAF SITES AT 16.12Z TAF ISSUANCE AS WINDS ARE EXPECTED TO  
INCREASE SHORTLY AFTER ISSUANCE FROM WEST TO EAST. HIGHEST WIND  
GUSTS EXPECTED TO REMAIN WEST OF THE MISSISSIPPI RIVER  
AFFECTING SMALLER AIRPORTS LOCALLY IN NORTHEAST IOWA AND  
SOUTHEAST MINNESOTA AS WELL AS KRST TAF SITE. INITIAL  
PRECIPITATION AND LOW STORM CHANCES SHIFT NORTHEAST IN A NARROW  
BAND FROM NORTHEAST IOWA INTO CENTRAL WISCONSIN, AFFECTING  
SMALLER AIRPORTS SOUTHEAST OF KLSE TAF SITE. SUBSEQUENT  
WIDESPREAD PRECIPITATION FILLS IN FROM NORTHWEST TO SOUTHEAST  
THIS EVENING INTO THE OVERNIGHT. THUNDER CHANCES ARE LOW BUT NOT  
OUT OF THE QUESTION. MVFR CEILINGS FILL IN TOWARDS THE END OF  
THE 16.12Z TAF PERIOD MOST LIGHTLY AFFECTING THE NORTHERN HALF  
OF THE LOCAL FORECAST AREA FROM SOUTHEAST MINNESOTA THROUGH  
WEST-CENTRAL WISCONSIN. HIGHEST CONFIDENCE LIES NORTH OF  
INTERSTATE 90, I.E., JUST ON THE EDGE OF KLSE AND KRST TAF  
SITES.  
 
 
   
ARX WATCHES/WARNINGS/ADVISORIES  
 
WI...NONE.  
MN...NONE.  
IA...NONE.  
 
 
 
 
 
DISCUSSION...RIECK  
AVIATION...JAR  
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