951  
FXUS63 KGRB 162326  
AFDGRB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREEN BAY WI  
626 PM CDT FRI MAY 16 2025  
 
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE  
   
KEY MESSAGES  
 
- SCATTERED SHOWERS AND THUNDERSTORMS THROUGH MID-EVENING,  
PARTICULARLY ACROSS EASTERN WISCONSIN. ISOLATED SEVERE IS  
POSSIBLE. DIMINISHING PRECIP/STORM CHANCES AFTER SUNSET.  
 
- SOMEWHAT GLOOMY ON SATURDAY WITH COOL NORTHWEST WINDS, CLOUDY  
SKIES, AND ISOLATED SHOWERS.  
 
- COOL TREND CONTINUES INTO MUCH OF NEXT WEEK.  
 
 
   
DISCUSSION  
 
ISSUED AT 352 PM CDT FRI MAY 16 2025  
 
MAIN FOCUS IS ONGOING THUNDERSTORMS ALONG WITH SYNOPTIC WINDS.  
ISOLATED SHOWERS DEVELOPED IN CENTRAL WI EARLY THIS AFTERNOON AND  
QUICKLY GREW INTO A BROKEN LINE OF THUNDERSTORMS TRACKING  
NORTHEAST--MAINLY ACROSS EASTERN AND NORTHEAST WI. THESE WERE  
MAINLY THE RESULT OF DAYTIME HEATING LEADING TO AN AREA OF  
INSTABILITY, WITH MUCAPE OF 400-1000 J/KG, PARTICULARLY IN THE  
EAST. THERE IS ALSO A SMALL SHORTWAVE AHEAD OF THE MAIN UPPER LOW,  
ALONG WITH SOME INFLUENCE FROM THE LFQ OF THE UPPER JET AIDING IN  
LARGE SCALE ASCENT. STRONG WINDS HAVE BEEN THE MAIN THREAT WITH  
INVERTED V SOUNDINGS SHOWING MIXING UP TO AS HIGH AS 8-9KFT, WHERE  
SYNOPTIC WIND ARE AROUND 50 KTS. SURFACE GUSTS NEAR 55MPH WERE  
REPORTED WITH THE FIRST SHOWERS IN PORTAGE CO. SPOTTER REPORTS  
SINCE THEN HAVE BEEN LIMITED, BUT RADAR AND ATMOSPHERIC CONDITIONS  
WOULD SUGGEST GUSTS TO 60MPH REMAIN POSSIBLE WITHIN ANY  
THUNDERSTORMS, OR EVEN STRONG SHOWERS. ADDITIONALLY, FREEZING  
LEVELS ARE QUITE LOW NEAR 9000 FT, WITH 50DBZ TO ONLY ~22000 FT  
NEEDED FOR 1" HAIL. SOME OF THE STORMS HAVE SURPASSED THIS, SO  
HAIL UP TO AROUND 1" REMAINS POSSIBLE WITHIN THE STRONGEST STORMS  
AS WELL.  
 
THE HRRR HAS BEEN THE MOST RELIABLE WITH TRENDS TODAY. WILL  
CONTINUE TO FOLLOW ITS GENERAL OUTPUT THROUGH THE EVENING. THIS  
INDICATES THE ONGOING STORMS CONTINUING TO TRACK NORTHEAST, WITH  
SOME ADDITIONAL DEVELOPMENT DOWNSTREAM WHICH IS CURRENTLY EVIDENT  
IN SOUTH-CENTRAL WI. THIS WOULD BRING ANOTHER BROKEN LINE OF  
SHOWERS/STORMS THROUGH THE EASTERN PARTS OF THE CWA LATE THIS  
AFTERNOON--HOWEVER, SOME QUESTION TO HOW MUCH INSTABILITY WILL BE  
AVAILABLE. REGARDLESS, WITH STRONG WINDS ABOVE THE SURFACE AND LOW  
FREEZING LEVELS WILL CONTINUE TO SEE AN ISOLATED SEVERE THREAT  
THROUGH EARLY THIS EVENING. AFTER SUNSET EXPECT THE SEVERE AND  
THUNDER THREAT TO GREATLY DIMINISH, WITH SOME ISOLATED TO  
SCATTERED SHOWERS OVERNIGHT. WINDS WILL ALSO SUBSIDE OVERNIGHT.  
 
SATURDAY...UPPER LOW TRACKS ACROSS THE STATE EARLY, WITH SOME WEAK  
WRAP AROUND ENERGY BEHIND IT. THIS KEEPS A LOW CHANCE (10-20%) OF  
SHOWERS IN THE FORECAST, BUT MOST OF THE DAY WILL BE DRY. HOWEVER,  
COOLER, CLOUDY, AND BREEZY CONDITIONS ARE EXPECTED WITH NORTHWEST  
WINDS GUSTING TO 30-35 MPH AND IN THE MIDDLE 50S TO LOW 60S.  
THUNDER CHANCE IS VERY LOW WITH VIRTUALLY NO INSTABILITY.  
 
COOLER TREND CONTINUES SUNDAY AND INTO MOST OF NEXT WEEK WITH  
TEMPERATURES AT OR BELOW NORMAL. DRY WEATHER IS LIKELY SUNDAY AND  
MONDAY, WITH CHANCES FOR PRECIP ON TUE/WED. HOWEVER, MODELS ARE  
NOT IN AGREEMENT ON THE TRACK OF THAT SYSTEM, SO THE PRECIP COULD  
MISS WI TO THE SOUTH.  
 
 
   
AVIATION  
FOR 00Z TAF ISSUANCE  
ISSUED AT 625 PM CDT FRI MAY 16 2025  
 
SCATTERED SHOWERS AND THUNDERSTORMS WILL WIND DOWN THIS EVENING AS  
THEY PUSH EAST OF WISCONSIN. A COLD FRONT WILL TRACK THROUGH THE  
REGION THIS EVENING, WHICH WILL LOWER CIGS TO A MIX OF MVFR/IFR  
AROUND 06Z THROUGH SATURDAY MORNING. CIGS ARE EXPECTED TO IMPROVE  
A BIT SATURDAY AFTERNOON TO MVFR/VFR ACROSS EAST-CENTRAL  
WISCONSIN. WINDS WILL ALSO INCREASE AGAIN AND PEAK LATE SATURDAY  
MORNING THROUGH THE AFTERNOON WITH GUSTS UP TO 30 KTS.  
 
 
   
MARINE  
 
ISSUED AT 352 PM CDT FRI MAY 16 2025  
 
GUSTY SOUTH WINDS AND SCATTERED THUNDERSTORMS WILL CONTINUE  
THROUGH EARLY THIS EVENING. WINDS SUBSIDE A BIT OVERNIGHT, AND  
THEN INCREASE FROM THE NORTHWEST ON SATURDAY MORNING. THE STRONG  
WINDS, ALONG WITH HIGH WAVES, WILL CONTINUE THROUGH EARLY SATURDAY  
EVENING FOR BOTH THE BAY AND LAKE MICHIGAN NEARSHORE WATERS. NO  
CHANGES TO THE CURRENT SMALL CRAFT ADVISORY.  
 
 
   
GRB WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
DISCUSSION.....KLJ  
AVIATION.......KURIMSKI  
MARINE.........KLJ  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab WI Page
Main Text Page