830  
FXUS63 KGRB 161730  
AFDGRB  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREEN BAY WI  
1230 PM CDT SUN AUG 16 2026  
 
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE  
   
KEY MESSAGES  
 
- ISOLATED TO SCATTERED SHOWERS (10 TO 30% CHANCE) POSSIBLE  
MAINLY ALONG THE DOOR PENINSULA THIS AFTERNOON.  
 
- SHOWER AND STORM CHANCES (20 TO 50%) RETURN LATE MONDAY NIGHT,  
CONTINUING THROUGH TUESDAY. POTENTIAL FOR EXCESSIVE RAINFALL  
AND SEVERE WEATHER HAVE DECREASED.  
 
- DROUGHT CONDITIONS EXPECTED TO WORSEN DUE TO RAINFALL DEFICIT  
AND LITTLE TO NO CHANCES FOR WETTING RAIN IN THE FORECAST.  
 
 
   
DISCUSSION  
 
ISSUED AT 1200 PM CDT SUN AUG 16 2026  
 
THIS AFTERNOON... BRIEF SHOWER CHANCES REMAIN POSSIBLE THROUGH  
THIS AFTERNOON MAINLY ALONG THE DOOR PENINSULA AS WEAK FRONTAL  
BOUNDARY GRADUALLY SHIFTS EAST. WITH LITTLE TO NO UPPER SUPPORT  
AND LIMITED INSTABILITY DUE TO CLOUD COVER, HAVE FOR THE MOST PART  
KEPT THUNDER OUT OF THE FORECAST. INCREASING GRADIENT WINDS BEHIND  
THE FRONT MAY RESULT IN 20 MPH GUSTS ACROSS THE AREA THROUGH THIS  
AFTERNOON.  
 
MINIMAL SHOWER/STORM CHANCES... BETTER CHANCES FOR SCATTERED  
SHOWERS AND EMBEDDED THUNDER COME MONDAY THROUGH TUESDAY AS STOUT  
NORTHWEST FLOW BRINGS ANOTHER FRONT THROUGH THE UPPER MISSISSIPPI  
VALLEY. MOST RECENT SUITE OF MODEL RUNS RETAIN THE TREND OF  
QUICKER AND EARLIER FROPA LATE MONDAY NIGHT INTO TUESDAY MORNING;  
AS SUCH, EXCESSIVE RAINFALL AND SEVERE POTENTIAL HAVE GONE DOWN.  
REGARDLESS, AIRMASS BEHIND THE FRONT DOESN'T LOOK PARTICULARLY  
JUICY, WITH BETTER MOISTURE TRANSPORT FROM THE GULF REMAINING TO  
OUR SOUTHWEST ANYWAY. WPC HAS THUS SHUNTED BOTH THE SLIGHT AND  
MARGINAL ERO TO THE SOUTH, THOUGH MARGINAL RISK REMAINS  
ALONG/SOUTH OF HWY 10. ANY EXCESSIVE RAIN POTENTIAL WOULD LIKELY  
COME WITH TRAINING STORMS OR REPEATED SHOWERS. CANNOT RULE OUT THE  
POSSIBILITY OF A DIURNAL STORM OR TWO, POSSIBLY ON THE STRONGER  
SIDE, AS MODEST INSTABILITY (500 TO 700 J/KG) COINCIDES WITH 40+  
KNOTS OF BULK SHEAR DURING PEAK HEATING.  
 
COOLER AND MORE STABLE AIR FILTERS IN BEHIND THE FRONT ON  
WEDNESDAY, WITH TEMPERATURES STEADYING OUT IN THE UPPER 70S TO LOW  
80S. NEXT PERIOD OF CONCERN WOULD THEN BE FRIDAY INTO SATURDAY AS  
POTENT SHORTWAVE AND ATTENDANT FRONT TRAVERSE THE MIDWEST. THOUGH  
STORM PREDICTABILITY IS LOW THIS FAR OUT, ML GUIDANCE PAINTS A  
BROAD 5 TO 15% PROB SEVERE, SO WILL CONTINUE TO MONITOR.  
 
WORSENING DROUGHT CONDITIONS... FORECAST CONCERNS GRADUALLY SHIFT  
TO WORSENING DROUGHT CONDITIONS DUE TO THE LACK OF WETTING RAIN  
WE'VE RECEIVED RECENTLY. ADDITIONALLY, LITTLE TO NO RELIEF IS IN  
SIGHT AS BETTER JET DYNAMICS REMAIN TO OUR NORTH WITH GREATER  
MOISTURE RETURN/INSTABILITY RESERVE HOLED UP TO OUR SOUTH. AS OF  
AUGUST 11TH, THE MAJORITY OF WISCONSIN SITS IN D1 DROUGHT STATUS  
(MODERATE), WITH POCKETS OF D2 (SEVERE) DROUGHT ACROSS NORTHWEST  
AND NORTH-CENTRAL WISCONSIN WHERE THEY HAVE RECEIVED ONLY 25 TO  
50% OF NORMAL PRECIP OVER THE PAST 30 DAYS. IF CURRENT DRY SPELL  
CONTINUES, FIRE WEATHER CONCERNS COULD COME INTO PLAY DURING LATE  
SUMMER/EARLY FALL DUE TO LOW AFTERNOON RHS AND DRYING FUELS.  
 
 
   
AVIATION  
FOR 18Z TAF ISSUANCE  
ISSUED AT 1200 PM CDT SUN AUG 16 2026  
 
MVFR STRATUS DECK BEHIND THE FRONT PERSISTS OVER THE NORTHWEST  
HALF OF THE STATE AS OF EARLY THIS AFTERNOON, THOUGH IMPROVEMENT  
TO VFR STRATOCU IS EXPECTED AT ALL TERMINALS WITHIN THE NEXT FEW  
HOURS AS THE FRONT SHIFTS EAST. LOW MVFR/IFR STRATUS THEN  
INCREASES FROM THE NORTH LATE TONIGHT INTO MONDAY MORNING, THOUGH  
COULD BE SIMILAR SITUATION TO THIS MORNING WHERE PATCHY FOG AND  
LOCALLY REDUCED VSBYS END UP MANIFESTING.  
 
WINDS CONTINUE TO VEER AND INCREASE OUT OF THE NORTHWEST EARLY  
THIS AFTERNOON, WITH GUSTS TO 20 KNOTS POSSIBLE INTO THIS EVENING.  
WINDS THEN SUBSIDE OVERNIGHT, BECOMING LIGHT AND VARIABLE INTO  
MONDAY MORNING.  
 
 
   
GRB WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
 
DISCUSSION.....GOODIN  
AVIATION.......GOODIN  
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