838  
FXUS63 KGRB 032251  
AFDGRB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREEN BAY WI  
551 PM CDT SAT OCT 3 2026  
 
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE  
   
KEY MESSAGES  
 
- CHANCE OF SHOWERS (40 TO 90%) AT TIMES THROUGH LATE TONIGHT.  
GREATEST CHANCES OF OVER 0.25 INCH OF RAIN FAR NORTH-CENTRAL WI.  
OTHERWISE, MAINLY DRY THROUGH NEXT WEEK.  
 
- AREAS OF FROST ACROSS NORTHERN WISCONSIN BOTH SUNDAY AND MONDAY  
NIGHTS. GREATEST CHANCE FOR A WIDESPREAD FROST/FREEZE EVENT  
WILL BE SUNDAY NIGHT.  
 
 
   
DISCUSSION  
 
ISSUED AT 101 PM CDT SAT OCT 3 2026  
 
RAIN CHANCES THROUGH SUNDAY...WEAK WARM AIR ADVECTION HAS BEEN MAIN  
TRIGGER FOR ISOLATED LIGHT SHOWERS SEEN SO FAR TODAY OVER WI.  
EXPECT A FEW SHOWERS THROUGH LATE THIS AFTERNOON ESPECIALLY  
NORTH-CENTRAL ON TAIL OF WAVE CROSSING LAKE SUPERIOR AND JUST  
AHEAD OF WEAK ELEVATED INSTABILITY. THUNDER RISK DOES APPEAR TO  
STAY CONFINED TO FAR WESTERN WI. BETTER PUSH FOR RAIN SHOWERS  
MOVES THROUGH THIS EVENING AS SHORTWAVE TROUGH AND STRONGER  
FORCING SLIDE THROUGH. DECENT AGREEMENT THAT NORTH-CENTRAL SEES  
THE MOST RAIN BY DAYBREAK SUNDAY WITH OVER 0.25 INCH, BUT MAINLY  
LESS THAN 0.50 INCH. THOUGH CHANCES HAVE INCREASED INTO SOUTH AND  
EASTERN AREAS AS WELL LATE EVENING AND OVERNIGHT, THE RAIN AMOUNTS  
WILL BE MOSTLY LESS THAN 0.15 INCH. RAIN SHIFTS EAST OF AREA AFTER  
4A SUNDAY AS WEAK COLD FRONT MOVES THROUGH. NORTHWEST FLOW ACROSS  
LAKE SUPERIOR COULD SQUEEZE A FEW SPRINKLES OUT OVER FAR NORTH  
FROM A SHALLOW STRATOCU DECK, BUT MARGINAL OVER-WATER INSTABILITY  
AND SHALLOW MOISTURE/LOW INVERSION HEIGHT WILL KEEP MAIN IMPACT  
TO LINGERING CLOUDS IN THE MORNING. BY AFTERNOON, SKIES SHOULD  
BECOME MOSTLY SUNNY, EVEN UP NORTH.  
 
FROST/FREEZE POTENTIAL...AFTER A REPRIEVE FROM FROST/FREEZE ISSUES  
TONIGHT DUE TO THE CLOUDS/RAIN MOVING THROUGH, ARRIVAL OF HIGH  
PRESSURE RIDGE AND CLEARING LEADS TO ANOTHER ROUND OF FROST/FREEZE  
SUNDAY NIGHT AND AGAIN MONDAY NIGHT, THEN AGAIN LATER THIS WEEK  
OVER THE NORTH. FOR SUNDAY NIGHT, NBM SHOWING SIMILAR FOOTPRINT  
TO WHAT OCCURRED THIS MORNING FOR TEMPS LESS THAN 36F, WITH A  
40-80% CHANCE OF TEMPERATURES BELOW 33 OVER THE NORTHERN TIER OF  
COUNTIES. GFS MOS GUIDANCE POINTS TO SUB-FREEZING TEMPS AS WELL.  
MONDAY NIGHT PRETTY SIMILAR, THOUGH WITH CENTER OF HIGH SHIFTING  
EAST, GREATEST RISK OF TEMPERATURES BELOW 33 IS SHUNTED TOWARD  
FAR NORTHEAST WI, WITH LESS SIGNAL OVER NORTH-CENTRAL WI. EXPECT  
ADDITIONAL FROST/FREEZE HEADLINES TO BE ISSUED FOR BOTH NIGHTS.  
THOUGH NOT AS PRONOUNCED YET, ARRIVAL OF ANOTHER HIGH BRINGS MORE  
POTENTIAL FOR FROST/FREEZE OVER FAR NORTH LATE THIS WEEK AS WELL.  
 
EXTENDED...COLD FRONT COMES THROUGH ON WEDNESDAY, BUT LOOKS TOO  
STARVED FOR MOISTURE TO PRODUCE ANY RAIN. SHARPER NORTHWEST FLOW  
ALOFT AND STRONGER SHORTWAVE MAY DROP ACROSS LATE THIS WEEK, BUT  
STRONGEST LIFTS PROBABLY STAYS NORTH RESULTING IN LREF SHOWING  
LESS THAN 25% CHANCE OF SEEING EVEN A FEW HUNDREDTHS. MAYBE A BIT  
BETTER SHOT OF SOME RAIN BEYOND NEXT WEEKEND PER LREF AND AI  
GUIDANCE, BUT OVERALL AS MID SHIFT SAID, THE LONGER WE GO WITHOUT  
SIGNIFICANT RAIN, WE COULD START TO HAVE INCREASING FIRE WEATHER  
CONCERNS OVER THE NEXT SEVERAL WEEKS DUE TO CURRENT DROUGHT STATUS  
AND INCREASING FINE FUELS AS WE EXPERIENCE REPEATED FROST/FREEZE  
CONDITIONS.  
 
 
   
AVIATION  
FOR 00Z TAF ISSUANCE  
ISSUED AT 546 PM CDT SAT OCT 3 2026  
 
A COLD FRONT WILL BRING A BAND OF RAIN ACROSS NORTHERN WISCONSIN  
THIS EVENING INTO EARLY SUNDAY MORNING, ESPECIALLY NORTH OF  
HIGHWAY 10. THE MOST NOTABLE CHANGE TO THE FORECAST WAS TO ADD  
WIND SHEAR THIS EVENING INTO EARLY SUNDAY MORNING FOR ALL THE  
TAF SITES 220-230 DEGREES AT 35 TO 40 KNOTS. AS THE RAIN EXITS  
THE AREA, LOW CLOUDS IN THE MVFR CATEGORY WILL LIKELY DEVELOP  
ACROSS THE NORTH, IMPACTING KRHI. UNCERTAINTY EXISTS IF CLOUD  
BASES WOULD BE IN THE MVFR CATEGORY AT KAUW/KCWA/KGRB/KATW/KMTW  
LATER TONIGHT. OTHERWISE, GUSTY NORTHWEST WINDS CAN BE  
EXPECTED SUNDAY, ESPECIALLY UNTIL MID AFTERNOON WITH SOME  
LOCATIONS GUSTING BETWEEN 20 AND 25 KNOTS. WINDS WILL QUICKLY  
SUBSIDE BY 00Z MONDAY.  
 
 
   
MARINE  
 
ISSUED AT 101 PM CDT SAT OCT 3 2026  
 
INCREASING SOUTHERLY WINDS INTO THIS EVENING WILL RESULT IN  
CONDITIONS HAZARDOUS TO SMALL CRAFT DEVELOPING ALONG THE  
NEARSHORE WATERS OF LAKE MICHIGAN INTO EARLY THIS EVENING, AND  
LASTING INTO SUNDAY MORNING. SOUTHWEST WINDS WILL GUST TO 25  
KNOTS, WITH WAVES BUILDING TO 4 TO 6 FT, HIGHEST NEAR DEATH'S  
DOOR AND THE LAKE SIDE OF WASHINGTON ISLAND.  
 
 
   
GRB WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
DISCUSSION.....JLA  
AVIATION.......ECKBERG  
MARINE.........JLA  
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