019  
FXUS63 KMKX 151136  
AFDMKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI  
636 AM CDT SAT AUG 15 2026  
   
KEY MESSAGES  
 
- SCATTERED SHOWERS POSSIBLE THIS MORNING, ESPECIALLY ALONG AND  
SOUTH OF I-94. ADDITIONAL SHOWER AND STORM POTENTIAL OVERNIGHT  
INTO SUNDAY, BUT PLENTY OF DRY TIME FOR THE REST OF THE  
WEEKEND.  
 
- HIGH SWIM RISK TODAY FOR LAKE MICHIGAN BEACHES IN MILWAUKEE,  
OZAUKEE, AND SHEBOYGAN COUNTIES.  
 
- DRY AND SEASONAL FOR THE START OF THE WEEK WITH STORM CHANCES  
RETURNING MIDWEEK.  
 
 
   
UPDATE  
 
ISSUED 640 AM CDT SAT AUG 15 2026  
 
PREVIOUS FORECAST REMAINS ON TRACK. THE HEAVIER RAINFALL  
OVERNIGHT/EARLY THIS MORNING HAS SET UP ALONG THE WARM FRONT  
STREWN ACROSS SOUTHERN IA AND CENTRAL IL/IN. WHILE THE HEAVIER  
RAINFALL IS FURTHER SOUTH, THERE IS STILL THE POTENTIAL FOR  
SHOWERS AND EVEN AN ISOLATED STORM THROUGH THE MORNING FOR AREAS  
AROUND THE WI/IL BORDER. AREAS NORTH OF I-94 MAY SEE A FEW  
SCATTERED LIGHT SHOWERS, BUT EXPECT PREDOMINATELY DRY  
CONDITIONS. MAY SEE SOME ISOLATED ACTIVITY THROUGH THE DAY AS  
THE LOW PRESSURE WORKS ITS WAY THROUGH THE AREA, BUT MAINLY  
EXPECTING DRY CONDITIONS THIS AFTERNOON WITH BETTER POTENTIAL  
FOR ADDITIONAL SHOWER AND STORM DEVELOPMENT OVERNIGHT INTO  
SUNDAY MORNING.  
 
WAGNER  
 
 
   
SHORT TERM  
 
ISSUED 100 AM CDT SAT AUG 15 2026  
 
TODAY THROUGH SUNDAY:  
 
THE LATEST MODEL GUIDANCE AND SATELLITE / RADAR TRENDS AFFIRM THAT  
THE VAST MAJORITY OF CONVECTION THIS MORNING WILL CONTINUE TO  
ROLL SOUTH OF WI, PREDOMINANTLY IMPACTING IL. A FEW STRAY CELLS  
MAY LIFT AND DECAY INTO SOUTHERN WI, OR EVEN DEVELOP OVERHEAD  
WITH THE NORTHERN-MOST EDGE OF THE WAA, BUT COVERAGE SHOULD  
REMAIN SCATTERED TO ISOLATED. WITH MUCAPE 500 JOULES OR LESS,  
STORMS WILL BE WEAK FOR OUR AREA. PWAT OF 2" OR GREATER COULD  
MAKE THESE SHOWERS EFFICIENT RAIN-MAKERS, BUT THE EXPECTED  
SPARSE COVERAGE AND SHORT LIFECYCLE OUGHT TO LIMIT  
ACCUMULATIONS.  
 
SOME OF THE 00Z CAM GUIDANCE DEPICTS WIDELY SCATTERED SHOWERS  
WRAPPING AROUND THE BACK SIDE OF THE DEPARTED CONVECTIVE COMPLEX  
THIS AFTERNOON, YIELDING SOME CONTINUED SLIGHT RAIN CHANCES FOR  
SOUTHERN WI THIS AFTERNOON. OTHER GUIDANCE THAT DOESN'T SHOW THIS  
ACTIVITY ALLOWS SOME GAPS IN THE CLOUDS TO FORM THIS AFTERNOON,  
WITH A POTENTIAL EVENING ROUND OF SHOWERS OR EVEN WEAK STORMS THEN  
POSSIBLE. IN EITHER CASE, SHOULD BE MINIMALLY IMPACTFUL UNLESS  
INSTABILITY EXCEEDS THE CURRENT EXPECTATIONS (EX. THE CLOUDS PART  
EARLY AND ADDITIONAL SUNSHINE MAKES IT THROUGH).  
 
A COLD FRONT CROSSES THE REGION LATE TONIGHT INTO EARLY SUNDAY  
MORNING, YIELDING WIDESPREAD 25-45% CHANCES FOR SHOWERS AND  
THUNDERSTORMS. BY THE TIME IT ARRIVES, MUCAPE SHOULD BE GENERALLY  
1500 JOULES OR LESS (HREF MEAN IS BELOW 1,000 JOULES PREDAWN),  
WHICH IS PLENTY FOR SOME THUNDER, BUT WITH 0-6KM BULK SHEAR  
GENERALLY 20KT OR LESS PREDAWN, THE ODDS OF STRONG TO SEVERE  
STORMS ARE LOOKING VERY LOW AT THIS TIME. CHANCES DECLINE  
RAPIDLY PAST DAYBREAK SUNDAY, LEAVING PREDOMINANTLY DRY WEATHER  
THROUGH THE REST OF SUNDAY. THE INITIAL WIND SHIFT + FRONT WILL  
LEAVE THE HUMID AIR (70 DEGREE DEWPOINTS) IN PLACE FOR SUNDAY,  
AND WILL ALLOW SOME SUNSHINE TO MAKE IT THROUGH THE CLOUDS,  
POTENTIALLY ALLOWING THE SOUTHEAST HALF OF THE CWA TO BRIEFLY  
REACH 2,000 JOULES SBCAPE INTO MIDDAY SUNDAY, BUT BY THEN THE  
SURFACE FRONT IS FAR GONE, ALONG WITH THE 500MB TROUGH. KEEPING  
CHANCES LOW (ROUGHLY 20% OR LESS) FOR AFTERNOON REDEVELOPMENT.  
 
SHEPPARD  
 
 
   
LONG TERM  
 
ISSUED 100 AM CDT SAT AUG 15 2026  
 
SUNDAY NIGHT THROUGH FRIDAY:  
 
A SURFACE RIDGE OF HIGH PRESSURE PASSES OVERHEAD EARLY NEXT  
WEEK, LEADING TO DRY AND SLIGHTLY LESS HUMID CONDITIONS.  
TEMPERATURES HOLD CLOSE TO SEASONAL NORMS, DEWPOINTS FALL TO THE  
LOW / MID 60S.  
 
CHANCES FOR SHOWERS AND THUNDERSTORMS RETURN MIDWEEK AS A COLD  
FRONT / SURFACE PRESSURE TROUGH SWEEPS EASTWARD ACROSS THE  
MIDWEST. HIGH PRESSURE BUILDS INTO THE MIDWEST LATE IN THE WORK  
WEEK, YIELDING PREDOMINANTLY DRY WEATHER.  
 
SHEPPARD  
 
 
   
AVIATION  
 
ISSUED 640 AM CDT SAT AUG 15 2026  
 
SHOWER CHANCES CONTINUE THROUGH THE MORNING FOR TERMINALS CLOSER  
TO THE WI/IL BORDER, WHILE AREAS NORTH OF I-94 ARE LIKELY TO  
STAY PREDOMINATELY DRY THROUGH THE DAY. CANNOT COMPLETELY RULE  
OUT AN ISOLATED STORM OR TWO, BUT CHANCES REMAIN VERY LOW.  
ADDITIONALLY, LOWER MVFR CEILINGS ARE LOOKING TO SPREAD INTO  
SOUTHERN WI THROUGH THE MORNING AND CONTINUE THROUGH A GOOD  
CHUNK OF THE DAY AHEAD OF THE APPROACHING SYSTEM. WINDS WILL  
GRADUALLY PICK UP AND SHIFT MORE SOUTHEASTERLY AS WELL. MAY SEE  
A BRIEF PERIOD OF IMPROVEMENT IN CEILING HEIGHTS LATER THIS  
AFTERNOON/EVENING, BUT ADDITIONAL SCATTERED SHOWER AND STORM  
CHANCES RETURN TONIGHT INTO SUNDAY AS A COLD FRONT PUSHES  
THROUGH THE REGION.  
 
WAGNER  
 
 
   
MARINE  
 
ISSUED 100 AM CDT SAT AUG 15 2026  
 
SYNOPSIS:  
PERIODS OF SHOWERS AND STORMS CONTINUE OVER THE SOUTHERN HALF OF  
LAKE MICHIGAN TODAY AND TONIGHT AS A FRONT REMAINS STALLED SOUTH  
OVER ILLINOIS AND INDIANA. LOW PRESSURE OF 29.8 INCHES OVER KANSAS  
WILL TRACK TO THE NORTHEAST THIS MORNING, THEN DUE EAST TOWARD  
SOUTHERN LAKE MICHIGAN THIS EVENING. THIS LOW SHOULD HELP TO BUMP  
UP WINDS AND WAVES ACROSS THE SOUTHERN TWO THIRDS OF LAKE MICHIGAN  
THROUGH THE DAYTIME HOURS TODAY, DECELERATING TONIGHT AS IT CLOSES  
IN. A COLD FRONT WILL THEN SWEEP ACROSS THE LAKE LATE TONIGHT INTO  
SUNDAY MORNING, WITH CHANCES FOR SHOWERS AND WEAK STORMS. A LIGHT  
NORTHWEST BREEZE ARRIVES WITH THE FRONT INTO SUNDAY.  
 
BEYOND THIS SYSTEM, A BROAD RIDGE OF HIGH PRESSURE OF 30.1 INCHES  
WILL PUSH INTO THE GREAT LAKES EARLY NEXT WEEK BEFORE ANOTHER  
POTENTIAL FRONT MOVES THROUGH THE REGION MIDWEEK.  
 
NEARSHORE ZONES:  
A SMALL CRAFT ADVISORY IS IN EFFECT FOR ZONES NORTH OF NORTH POINT  
LIGHTHOUSE FROM 8 AM TO 7 PM CDT TODAY DUE TO BREEZY SOUTHEAST  
WINDS AND HIGH WAVES. WAVES ARE EXPECTED TO APPROACH THE 3 TO 6 FT  
MARK. WINDS ARE LESS CERTAIN, BUT SHOULD BE BETWEEN 10 AND 20 KT  
SUSTAINED WITH GUSTS UP TO 25 KT. HIGHEST CONFIDENCE IN THESE  
GUSTS IS TOWARDS CENTRAL LAKE MI, ADJACENT TO SHEBOYGAN.  
 
SHEPPARD  
 
 
   
MKX WATCHES/WARNINGS/ADVISORIES  
 
WI...BEACH HAZARDS STATEMENT...WIZ052-WIZ060-WIZ066 UNTIL 7 PM  
SATURDAY.  
 
LM...SMALL CRAFT ADVISORY...LMZ643-LMZ644 UNTIL 7 PM SATURDAY.  
 
 
 
 
 
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