183  
FXUS63 KGRR 251845  
AFDGRR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GRAND RAPIDS MI  
245 PM EDT SAT APR 25 2026  
   
KEY MESSAGES
 
 
- DRY UNTIL CHANCES FOR RAIN AND THUNDERSTORMS MONDAY NIGHT  
 
- MAINLY DRY AND COOLER FOR THE REMAINDER OF NEXT WEEK  
 

 
   
DISCUSSION
 
 
ISSUED AT 245 PM EDT SAT APR 25 2026  
 
- DRY UNTIL CHANCES FOR RAIN AND THUNDERSTORMS MONDAY NIGHT  
 
UPPER LEVEL RIDGING AND HIGH PRESSURE WILL REMAIN IN PLACE THROUGH  
THE WEEKEND RESULTING IN DRY CONDITIONS. SOUTHWEST FLOW MOVES IN  
MONDAY AHEAD OF THE SHORTWAVE TROUGH. UPPER LEVEL DIVERGENCE,  
POSITIVE VORTICITY ADVECTION, AND THE LOW LEVEL JET LINE UP FOR  
LATE MONDAY AFTERNOON INTO MONDAY NIGHT. THERE WILL BE PLENTY OF  
SHEAR IN PLACE WITH THE 50 KNOT LOW LEVEL JET WITH WINDS UP TO 70  
KNOTS IN THE MID LEVELS. THE QUESTION ON OUR SEVERE POTENTIAL WILL  
LARGELY BE UP TO HOW MUCH INSTABILITY IS AVAILABLE. NBM MEAN  
SBCAPE HAS INSTABILITY RANGING FROM A FEW HUNDRED TO A COUPLE  
HUNDRED J/KG TOWARD US-10 TO NEAR 1000 J/KG TOWARD THE I-94  
CORRIDOR. IF THESE INSTABILITY VALUES REMAIN THE SAME OR INCREASE,  
THE SPC OUTLOOK WOULD LIKELY TREND UPWARD AS WE GET CLOSER. AFTER  
THE INITIAL ROUND OF THUNDERSTORMS MONDAY NIGHT, SOME LINGERING  
RAIN SHOWERS ARE POSSIBLE INTO TUESDAY MORNING.  
 
- MAINLY DRY AND COOLER FOR THE REMAINDER OF NEXT WEEK  
 
OVERALL WE'LL REMAIN UNDER THE UPPER LEVEL TROUGH WITH THE  
POTENTIAL FOR A COUPLE SHORTWAVE TROUGHS TO MOVE THROUGH. THESE  
TROUGHS COULD BRING SOME CHANCES (20 PERCENT) FOR LIGHT SHOWERS,  
BUT MOISTURE IS LIMITED WITH PRECIPITABLE WATER VALUES REMAINING  
LOW. HIGHS THROUGH THE WEEK ARE EXPECTED TO BE IN THE 50S WITH  
LOWS IN THE 30S BRINGING THE RISK FOR A WIDESPREAD FROST.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z SUNDAY/
 
 
ISSUED AT 111 PM EDT SAT APR 25 2026  
 
SKIES HAVE ALREADY CLEARED AT MKG/GRR/AZO WITH BTL LIKELY TO  
FOLLOW IN THE NEXT 1-2 HOURS AS THE CLOUD EDGE SLOWLY WORKS EAST.  
LAN AND JXN WILL BE MVFR MUCH OF THE REST OF THE DAY, POTENTIALLY  
NOT BREAKING INTO VFR AT ALL UNTIL MID DAY SUNDAY. MVFR CIGS  
REDEVELOP/PERSIST OVERNIGHT AT ALL TERMINALS EXCEPT GRR/MKG BEFORE  
SCATTERING OUT SUNDAY AS TEMPS WARM AND LOW-LEVEL MOISTURE  
DECREASES.  
 

 
   
MARINE
 
 
ISSUED AT 245 PM EDT SAT APR 25 2026  
 
WINDS ARE OVERACHIEVING THIS AFTERNOON AND WITH AN EXPECTED TREND  
UPWARD, EXPECT GUSTS TO BE IN THE 25 TO 30 KNOT RANGE UNTIL THIS  
EVENING. WITH THIS CHANGE HAVE ISSUED A SMALL CRAFT ADVISORY UNTIL  
8PM. WINDS ARE EXPECTED TO WEAKEN AND TURN MORE EASTERLY TONIGHT  
INTO SUNDAY WITH LOW WAVE HEIGHTS.  
 
MONDAY WINDS TURN TO THE SOUTHWEST WITH A CHANCE FOR THUNDERSTORMS  
TO MOVE IN DURING THE LATE AFTERNOON AND EVENING. SMALL CRAFT  
ADVISORY CONDITIONS ARE LIKELY FOR MONDAY INTO TUESDAY. WINDS  
SHOULD REMAIN BELOW GALES DUE TO THE COLD WATERS, HOWEVER STORMS  
COULD BE STRONG TO SEVERE AND MIX DOWN STRONGER WINDS FROM ALOFT.  
 

 
   
GRR WATCHES/WARNINGS/ADVISORIES
 
 
MI...NONE.  
MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LMZ844>849.  
 

 
 

 
 
DISCUSSION...RAH  
AVIATION...THOMAS  
MARINE...RAH  
 
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