428  
FXUS63 KGRB 191745  
AFDGRB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREEN BAY WI  
1245 PM CDT TUE MAY 19 2026  
 
UPDATED AVIATION PORTION FOR 18Z TAF ISSUANCE  
   
KEY MESSAGES
 
 
- ISOLATED STRONG WINDS GUSTS ARE POSSIBLE EARLY THIS MORNING AS  
SCATTERED THUNDERSTORMS MOVE ACROSS THE AREA.  
 
- FROST OR FREEZE HEADLINES MAY BE NEEDED TUESDAY NIGHT AND  
WEDNESDAY NIGHT.  
 
- WARMING BACK UP THIS WEEKEND WITH RETURNING CHANCES FOR SHOWERS  
AND STORMS.  
 

 
   
DISCUSSION
 
 
ISSUED AT 138 AM CDT TUE MAY 19 2026  
 
SCATTERED THUNDERSTORMS WILL CONTINUE TO MOVE NORTHEAST ACROSS EAST-  
CENTRAL AND NORTHEAST WI EARLY THIS MORNING IN ASSOCIATION WITH A  
PASSING MID-LEVEL SHORT-WAVE AND STRENGTHENING LLJ. THE RISK FOR  
SEVERE THUNDERSTORMS IS VERY LOW GIVEN WEAK INSTABILITY, HOWEVER, ANY  
STORM MAY BE CAPABLE OF PRODUCING BRIEF WIND GUSTS OF 40-50 MPH AND  
SMALL HAIL. ON THE WESTERN BACK EDGE OF THESE STORMS SURFACE OBS  
FROM SE MN AND WESTERN WI ARE SHOWING 40-50 MPH WIND GUSTS OUT OF  
THE SOUTHEAST, INDICATIVE OF A WAKE LOW. AS THE PRECIPITATION ERODES  
TO THE EAST EXPECT THESE STRONGER WAKE LOW WINDS TO MAKE IT INTO  
CENTRAL WI OVER THE NEXT FEW HOURS.  
 
ANOTHER ROUND OF SHOWERS AND STORMS IS LIKELY LATER THIS MORNINGS AS  
A COLD FRONT, CURRENTLY SNAKING FROM FAR NW WI BACK TOWARD SOUTH-  
CENTRAL MN, SWEEPS ACROSS THE REGION. CAMS DO SHOW SOME WEAK  
INSTABILITY (100-300 J/KG) BUILDING AHEAD OF THE FRONT WHICH COULD  
SUPPORT AN ISOLATED STRONGER THUNDERSTORM, HOWEVER, THE RISK FOR ANY  
STORMS REACHING SEVERE LIMITS IS LOW. BEHIND THE FRONT STEEP LOW-  
LEVEL LAPSE RATES ASSOCIATED WITH THE CAA REGIME MAY SPUR ON ISOLATED  
SHOWERS THROUGH THIS AFTERNOON. ANY LINGERING SHOWERS SHOULD WANE  
THIS EVENING AS HIGH PRESSURE STARTS TO BUILD BACK INTO THE REGION.  
THE AREA SHOULD REMAIN UNDER THE INFLUENCE OF HIGH PRESSURE FOR THE  
REMAINDER OF THE WEEK LEADING TO DRY CONDITIONS.  
 
WITH THE HIGH OVERHEAD WEDNESDAY NIGHT AND A DRY AIR MASS IN PLACE  
(PWATS ~0.3") LOWS ARE FORECAST TO FALL NEAR FREEZING ACROSS  
NORTHERN WI WHICH MAY PROMPT THE NEED FOR FROST/FREEZE HEADLINES.  
 
THE NEXT CHANCE (30-50%) FOR SHOWERS AND THUNDERSTORMS ARRIVES THIS  
WEEKEND AS SOUTHERLY RETURN FLOW DELIVERS WARMER AND MORE MOIST AIR  
BACK TO THE REGION. GLOBAL ENSEMBLES AND LONG RANGE ML PRODUCTS ARE  
NOT HIGHLIGHTING MUCH OF SEVERE STORM WITH THIS SYSTEM AT THIS  
POINT.  
 

 
   
AVIATION
 
FOR 18Z TAF ISSUANCE  
ISSUED AT 1123 AM CDT TUE MAY 19 2026  
 
MVFR STRATUS DECK HAS PERSISTED OVER MOST OF THE FORECAST AREA  
THIS AFTERNOON AS THE COLD FRONT CONTINUES TO PROGRESS TO THE  
EAST. DOWNSLOPING NORTHWEST WINDS MAY HELP SCATTER OUT SOME OF THE  
LOWER CLOUDS LATER THIS AFTERNOON AND EVENING, WITH GRB, ATW, AND  
MTW EXPECTED TO LIFT TO VFR WITHIN THE NEXT FEW HOURS. BKN MVFR  
CIGS WILL LIKELY STICK AROUND IN/NEAR RHI FOR THE MAJORITY OF THE  
TAF PERIOD, THOUGH WINDOWS FOR IMPROVEMENT TO VFR WILL BE  
POSSIBLE.  
 
WINDS HAVE ALREADY SHIFTED TO THE WEST/NORTHWEST AS OF THIS  
AFTERNOON, WITH THE EAST-CENTRAL SITES EXPECTED TO SHIFT WITHIN  
THE NEXT HOUR OR TWO. GUSTS BETWEEN 20 AND 25 KNOTS WILL BE  
POSSIBLE THROUGH THIS AFTERNOON, BEFORE WINDS SUBSIDE THIS EVENING  
AND OVERNIGHT WITH THE LOSS OF DAYTIME MIXING.  
 

 
   
GRB WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
DISCUSSION.....GK  
AVIATION.......GOODIN  
 
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