936  
FXUS63 KGRB 182046  
AFDGRB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREEN BAY WI  
346 PM CDT FRI JUL 18 2025  
 
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE  
   
KEY MESSAGES  
 
- SHOWERS AND SCATTERED THUNDERSTORMS EXPECTED LATE TONIGHT INTO  
SATURDAY, THEN PLEASANT CONDITIONS RETURN SATURDAY NIGHT THROUGH  
MONDAY. SMOKE FROM CANADIAN WILDFIRES RETURNS SATURDAY NIGHT  
INTO SUNDAY.  
 
- AN ACTIVE PATTERN IS EXPECTED DURING THE MIDDLE OF NEXT WEEK,  
WITH PERIODIC CHANCES OF SHOWERS AND THUNDERSTORMS. STRONG  
STORMS AND HEAVY RAIN WILL BE POSSIBLE AT TIMES.  
 
 
   
DISCUSSION  
 
ISSUED AT 346 PM CDT FRI JUL 18 2025  
 
SKIES WERE MOSTLY CLOUDY OVER NC WI THIS AFTERNOON, WHILE PARTLY  
CLOUDY CONDITIONS WERE OBSERVED ELSEWHERE. A SHORT-WAVE WAS  
TRACKING THROUGH FAR NORTHERN WI, BRINGING A FEW LIGHT SPRINKLES  
OR VIRGA TO AREAS NEAR THE U.P. BORDER. TEMPERATURES WERE  
SEASONABLY COOL; RANGING FROM THE UPPER 60S FAR NORTH AND NEAR  
LAKE MICHIGAN TO THE LOWER TO MIDDLE 70S ELSEWHERE.  
 
EXPECT MAINLY DRY CONDITIONS TO PREVAIL THIS EVENING. H8 WAA  
DEVELOPING AHEAD OF AN APPROACHING COLD FRONT, AND UPPER FORCING  
FROM A WEAK SHORT-WAVE OR JET STREAK, SHOULD GENERATE SHOWERS AND  
SCATTERED THUNDERSTORMS LATE TONIGHT, MAINLY WEST OF THE FOX  
VALLEY/LAKESHORE AREAS. MUCAPE (ALL ELEVATED) IS ONLY EXPECTED TO  
BE 300-700 J/KG, SO SEVERE WEATHER IS NOT EXPECTED. THE COLD  
FRONT WILL TRACK SOUTHEAST THROUGH THE FORECAST AREA ON SATURDAY,  
WITH SHOWERS AND EMBEDDED STORMS CONTINUING UNTIL IT SHIFTS SOUTH  
OF THE REGION LATE IN THE DAY. THINK THERE MAY BE ENOUGH CLOUD  
COVER AND SHOWERS AROUND TO LIMIT THE SEVERE THREAT, BUT CAPE OF  
1000-1500 J/KG ACROSS C/EC WI BEARS WATCHING, AS SUGGESTED BY THE  
SMALL SLIVER OF A MARGINAL SEVERE RISK SEEN ON THE SPC DAY 2  
OUTLOOK.  
 
HIGH PRESSURE BRINGS DRY AND PLEASANT CONDITIONS SATURDAY NIGHT  
THROUGH MONDAY. SMOKE FROM CANADIAN WILDFIRES WILL PUSH INTO  
THE FORECAST AREA SATURDAY NIGHT INTO SUNDAY. WHILE THE INITIAL  
SURGE SHOULD BE ALOFT, THERE IS SOME POTENTIAL FOR SURFACE-BASED  
SMOKE ON SUNDAY. AS SUCH, HAVE INCREASED SKY COVER A BIT SATURDAY  
NIGHT, AND ADDED PATCHY SMOKE TO THE FORECAST ON SUNDAY.  
 
ZONAL FLOW SETS UP ACROSS THE REGION FOR THE REST OF THE WORK  
WEEK, WITH VERY WARM AND MORE HUMID CONDITIONS RETURNING TO THE  
FORECAST AREA. TIMING AND LOCATION OF INDIVIDUAL DISTURBANCES  
(POSSIBLY CONVECTIVELY-INDUCED MCVS) WILL BE VERY DIFFICULT, SO  
SPECIFIC DETAILS ON POPS WILL BE INITIALLY LACKING. THERE IS SOME  
CONSENSUS THAT A COUPLE ROUNDS OF CONVECTION COULD DEVELOP AS A  
WARM FRONT LIFTS TOWARD THE REGION TUESDAY INTO TUESDAY NIGHT,  
FOLLOWED BY A COLD FRONTAL PASSAGE SOMETIME DURING THE WEDNESDAY  
TO THURSDAY TIME FRAME. DURING THIS MID-WEEK PERIOD, CAPE IS  
EXPECTED TO INCREASE TO 2-3K J/KG, SO A PERIOD OR TWO OF SEVERE  
STORMS COULD OCCUR. IN ADDITION, WITH PWATS INCREASING TO AROUND 2  
INCHES AND SURFACE DEW POINTS RISING INTO THE MIDDLE 60S TO  
MIDDLE 70S, HEAVY RAINFALL WILL ALSO BE A DISTINCT POSSIBILITY.  
LOOK FOR HIGHS TO REACH WELL INTO THE 80S, AND HEAT INDICES COULD  
GET AS HIGH AS THE UPPER 80S TO LOWER 90S IN PARTS OF C/EC WI.  
 
 
   
AVIATION  
FOR 18Z TAF ISSUANCE  
ISSUED AT 113 PM CDT FRI JUL 18 2025  
 
AS PREVIOUSLY FORECAST, A FEW/SCT CU FIELD WITH BASES OF 3500-5000  
FT AGL DEVELOPED EARLY THIS AFTERNOON SOUTH OF A GRB TO ISW LINE.  
MID AND HIGH CLOUDS ALSO MOVED INTO NORTH-CENTRAL WI EARLY THIS  
AFTERNOON AHEAD OF A DEVELOPING LOW PRESSURE SYSTEM. THIS SYSTEM  
IS EXPECTED TO SLOWLY TRACK ACROSS THE STATE THROUGH THE END OF  
THIS TAF PERIOD, BRINGING ISOLATED TO SCATTERED SHOWERS, MVFR/IFR  
CIGS, AND MVFR VSBYS FROM NORTHWEST TO SOUTHEAST. MESO MODELS ARE  
NOT IN AGREEMENT WITH THE TIMING OR PLACEMENT OF THE SHOWERS,  
LEAVING LOW CONFIDENCE IN WHEN THE SHOWERS WILL MOVE OVER A  
SPECIFIC TAF SITE. HOWEVER, A GENERAL CONSENSUS HAS THE SHOWERS  
ARRIVING SOMETIME AFTER 06Z SAT FOR ALL TAF SITES. MAINLY USED  
PROB30 GROUPS AT ALL TAF SITES FOR THE SHOWERS WITH ANTICIPATED  
TIMING. THERE IS ALSO POTENTIAL FOR THUNDER AT TIMES, BUT GIVEN  
THE LACK IN CONFIDENCE IN TIMING/PLACEMENT, OPTED TO NOT INCLUDE  
THUNDER, EXCEPT AT RHI WITH A PROB30 WHERE CONFIDENCE IS SLIGHTLY  
HIGHER FOR THUNDER TO OCCUR.  
 
THE PASSING SYSTEM IS EXPECTED TO CAUSE A WIND SHIFT FROM THE  
PREVAILING SOUTH/SOUTHEAST TO WEST/NORTHWEST DURING SATURDAY  
MORNING, BUT WINDS WILL REMAIN AROUND 5-15 KTS.  
 
 
   
GRB WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
DISCUSSION.....KIECKBUSCH  
AVIATION.......KRUK  
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