763  
FXUS63 KGRB 090248 AAA  
AFDGRB  
 
AREA FORECAST DISCUSSION...UPDATED  
NATIONAL WEATHER SERVICE GREEN BAY WI  
948 PM CDT WED APR 8 2026  
 
NEW INFORMATION ADDED TO UPDATE SECTION  
   
UPDATE  
 
ISSUED AT 946 PM CDT WED APR 8 2026  
 
SWATH OF RAIN JUST AHEAD OF COLD FRONT IS QUICKLY SHIFTING EAST  
THIS EVENING, PRETTY MUCH ON TRACK WITH GOING FORECAST. NO THUNDER  
YET, BUT STILL COULD HAVE A RUMBLE OF THUNDER THROUGH MIDNIGHT  
OVER EASTERN WI. GUSTY SOUTH WINDS FROM EARLIER THAT GUSTED TO  
AROUND 50 MPH HAVE DIMINISHED. DO EXPECT A PUSH OF GUSTY W/NW  
WINDS LATER TONIGHT THROUGH DAYBREAK ON THURSDAY BEHIND THE FRONT.  
RAINFALL AMOUNTS HAVE STAYED IN CHECK THUS FAR, WITH MOST AMOUNTS  
UNDER 0.25 INCH, AND ISOLATED SPOTS 0.30-0.40 INCH.  
 
AS THE WINDS HAVE DIMINISHED, HAVE DROPPED THE GALE WARNING ON  
LAKE MICHIGAN.  
 
 
   
KEY MESSAGES  
 
- POTENTIAL FOR HEAVY RAINFALL AND THUNDERSTORMS THIS WEEKEND INTO  
EARLY NEXT WEEK. 1 TO 1.5" OF QPF EXPECTED, WITH UP TO 2"  
POSSIBLE IN SPOTS. STRONG OR SEVERE THUNDERSTORMS THEN POSSIBLE  
MONDAY INTO TUESDAY.  
 
- MINOR FLOODING CONTINUES ALONG A FEW RIVERS, THOUGH RUNOFF FROM  
MELTING SNOW IN THE UPPER PENINSULA PAIRED WITH HEAVY RAIN MAY  
RESULT IN MORE WIDESPREAD AND SIGNIFICANT FLOODING THIS WEEKEND  
INTO EARLY NEXT WEEK.  
 
 
   
DISCUSSION  
 
ISSUED AT 958 AM CDT WED APR 8 2026  
 
RADAR SHOWS ANY REMNANTS OF THE WINTRY MIX FROM THIS MORNING  
DEPARTING THE AREA TO THE EAST AS OF EARLY THIS AFTERNOON.  
HOWEVER, WE WILL ONLY BE AFFORDED A BRIEF DRY SPELL BEFORE BETTER  
SATURATION RETURNS LATE THIS AFTERNOON INTO THIS EVENING WITH THE  
PASSAGE OF A POTENT MID-LEVEL SHORTWAVE AND TANDEM COLD FRONT.  
THIS SHOULD BRING AN ADDITIONAL 0.25 TO 0.5" OF QPF ACROSS THE  
FORECAST AREA THROUGH THURSDAY MORNING. NARROW CORRIDOR OF  
ELEVATED INSTABILITY (200 TO 300 J/KG) RIGHT ALONG THE FRONT  
WOULD SUGGEST THAT A RUMBLE OR TWO OF THUNDER WOULDN'T BE OUT OF  
THE QUESTION THIS EVENING, THOUGH NO ORGANIZED STORMS ARE  
EXPECTED.  
 
TRANSIENT SHORTWAVE ENERGY PAIRED WITH MID-LEVEL FGEN WILL BRING  
ANOTHER QUICK-HITTING ROUND OF LIGHT RAIN TO NORTHEAST WISCONSIN  
THURSDAY NIGHT INTO FRIDAY MORNING. MOST AREAS SHOULD SEE UNDER A  
TENTH OF QPF, WITH HIGHEST AMOUNTS APPROACHING 0.2" OVER EAST-  
CENTRAL WISCONSIN.  
 
WEEKEND RAIN/STORM CHANCES... PREVAILING SOUTHERLY FLOW AND A  
WIDE OPEN GULF WILL PROMOTE A PERIOD OF PROLONGED ACTIVE WEATHER  
THROUGH NEXT WEEK. OF PARTICULAR CONCERN WILL BE THE MONDAY INTO  
TUESDAY PERIOD AS A DEEPENING SURFACE LOW AND ATTENDANT COLD  
FRONT TRACK THROUGH THE UPPER MISSISSIPPI VALLEY. PWATS RANGING  
FROM 1 TO 1.25" WOULD SUPPORT A DECENT PERIOD OF MODERATE TO HEAVY  
RAIN DURING THIS TIME, WITH PROBABILISTIC GUIDANCE SHOWING A 10  
TO 30% CHANCE FOR RECEIVING 1.5" OF QPF THROUGH TUESDAY MORNING.  
MODEST INSTABILITY (~1,000 TO 1,200 J/KG MUCAPE) AND APPRECIABLE  
DEEP LAYER SHEAR (45 TO 55 KNOTS) MAY RESULT IN THE DEVELOPMENT OF  
STRONG OR EVEN SEVERE STORMS LATE MONDAY INTO TUESDAY, THOUGH  
THERE ARE STILL TIMING DISCREPANCIES WITHIN THE ENSEMBLES  
REGARDING COLD FROPA. THIS WOULD LIKELY MAKE A DIFFERENCE IN  
WHETHER OR NOT SURFACE-BASED STORMS WOULD BE ABLE TO DEVELOP, AND  
IS WORTH MONITORING IN THE COMING DAYS. REGARDLESS, CSU AND NCAR  
MACHINE LEARNING ALGORITHMS HIGHLIGHT MUCH OF THE UPPER MIDWEST IN  
A 15 TO 30% PROB SEVERE OUT TO DAY 6.  
 
 
   
AVIATION  
FOR 00Z TAF ISSUANCE  
ISSUED AT 643 PM CDT WED APR 8 2026  
 
CONDITIONS ARE VFR THIS EVENING, BUT IT IS FAR FROM TRANQUIL WITH  
STRONG, GUSTY SURFACE WINDS (OVER 30 KTS AT TIMES SINCE LATE  
AFTERNOON) AND LLWS (SW AT 015 UP TO 50 KTS), NOT TO MENTION AREA  
OF RAIN SHIFTING OVER THE REGION THROUGH THIS EVENING JUST AHEAD  
OF A COLD FRONT. OVERALL, EXPECT BORDERLINE MVFR VSBY WITH THE  
RAIN, BUT OTHERWISE IT WILL REMAIN VFR. THE RAIN MOVES THROUGH  
QUICKLY AND SURFACE WINDS WILL BECOME NOT AS GUSTY THROUGH THE  
NIGHT AS WINDS SHIFT FROM S/SW TO W. EVENTUALLY TOWARD DAYBREAK ON  
THURSDAY THE LLWS WILL END.  
 
LATE TONIGHT INTO THURSDAY MORNING, SCT-BKN MVFR STRATOCU CLOUDS  
WILL MOVE INTO CENTRAL AND NORTH-CENTRAL WI (RHI, AUW, CWA).  
THE GREATEST CHANCES FOR PREVAILING MVFR CIGS WILL BE AT RHI  
TOWARD THE UPPER MICHIGAN BORDER. ELSEWHERE, SCATTERED VFR CLOUDS  
WILL PREVAIL THROUGH THE DAY. WINDS WILL BE FROM THE W/NW AND NOT  
AS GUSTY AS TODAY.  
 
 
   
HYDROLOGY  
 
ISSUED AT 958 AM CDT WED APR 8 2026  
 
MINOR FLOODING CONTINUES ON THE WOLF RIVER, PERSISTING FOR THE  
BETTER PART OF THE NEXT WEEK. FAST FLOWS AND BANKFULL CONDITIONS  
WERE OBSERVED ELSEWHERE, NAMELY ON THE OCONTO, MENOMINEE, AND  
WISCONSIN RIVERS. MOVING FORWARD, ACTIVE PATTERN WITH AMPLE  
MOISTURE SUPPLY WILL CONTINUE TO RESULT IN HYDRO CONCERNS FOR THE  
FORESEEABLE FUTURE, ESPECIALLY WITH PWATS NEARING ABSOLUTE MAX  
RELATIVE TO CLIMO WITH THE PASSAGE OF ANOTHER SYSTEM THIS  
WEEKEND. PROBABILITIES FOR RECEIVING 1.5" OF QPF CURRENTLY RANGE  
FROM 10 TO 30% DURING THIS TIME, WHICH WOULD ONLY EXACERBATE SOIL  
SATURATION AND PROMOTE RUNOFF. CONVECTIVELY-ENHANCED RAINFALL  
WOULD ALSO SUPPORT RIVER/STREAM RISES EARLY NEXT WEEK. AREA OF  
PARTICULAR CONCERN LOOKS TO BE THE MENOMINEE RIVER AND ITS  
TRIBUTARIES, WHERE A SIGNAL FOR MINOR AND EVEN MODERATE FLOODING  
EXISTS DUE TO THE ADDITIONAL INFLUENCE OF SNOWMELT FROM THE UPPER  
PENINSULA.  
 
 
   
GRB WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
UPDATE.........JLA  
DISCUSSION.....GOODIN  
AVIATION.......JLA  
HYDROLOGY......GOODIN  
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