313  
FXUS63 KGRR 211516  
AFDGRR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GRAND RAPIDS MI  
1116 AM EDT SAT MAY 21 2022  
 
LATEST UPDATE...  
UPDATE  
   
UPDATE
 
 
ISSUED AT 1116 AM EDT SAT MAY 21 2022  
 
WE ARE RAIN-FREE CURRENTLY ALTHOUGH MORE SHOWERS ARE NOSING  
NORTHEAST FROM CHICAGO/KENOSHA/MILWAUKEE AND ANOTHER BATCH NEAR  
VALPARAISO IS WORKING TOWARD I-94. SO DESPITE THE CURRENT LULL  
WILL NEED TO MAINTAIN AT LEAST CHANCE/SCATTERED SHOWERS IN THE  
FCST THIS AFTERNOON. THUNDER THREAT HAS LOWERED WITH MAIN MUCAPE  
GRADIENT NOW SOUTH AND EAST OF HERE. HOWEVER THERE IS STILL A FEW  
HUNDRED JOULES AVAILABLE PER RAP GUIDANCE AND A FEW LTG STRIKES  
NOTED CURRENTLY IN NRN IL SO WILL KEEP A SLGT CHC OF A TSTM THIS  
AFTERNOON (MAINLY SOUTH OF I-96). NO SVR WX EXPECTED SINCE WE'RE  
FIRMLY ON THE COOL/STABLE NRN SIDE OF THE SFC FRONT NOW.  
 

 
   
DISCUSSION
 
(TODAY THROUGH NEXT FRIDAY)  
ISSUED AT 324 AM EDT SAT MAY 21 2022  
   
..LULL IN PRECIPITATION TODAY, THEN AN INCREASE TONIGHT
 
 
REGIONAL RADAR SHOWS A BAND OF SHOWERS AND THUNDERSTORMS STRETCHING  
FROM SAGINAW BAY SOUTHWEST TO TULSA. THE BAND WAS SLOWLY SAGGING  
SOUTHEAST AND WAS ELEVATED IN NATURE BEHIND THE COLD FRONT THAT  
STRETCHES FROM FLINT TO NEAR JACKSON. FORECAST SOUNDINGS SHOW SOME  
ELEVATED INSTABILITY NEAR GRAND RAPIDS THROUGH 9 AM OR SO BEFORE THE  
THREAT MOVES EAST. CAMS SHOW PRECIP POTENTIAL WANING AS THE MORNING  
PROGRESSES AND ONE WAVE MOVES AWAY. AS THE FRONT STALLS NEAR TOLEDO,  
THE NEXT WAVE WILL RIDE NORTHEAST ALONG IT TONIGHT AND SPREAD  
SHOWERS AND STORMS INTO THE CWA...MAINLY SOUTH OF GRAND HAVEN TO  
ALMA LINE. THERE WILL BE MUCH LESS INSTABILITY TONIGHT AND SO MUCH  
OF THE PRECIP WILL BE SHOWERS WITH ISOLATED THUNDER.  
   
..DRY AND COOLER SUNDAY INTO NEXT WEEK
 
 
DESPITE SUNSHINE SUNDAY, A LARGE AREA OF HIGH PRESSURE WILL SETTLE  
OVER THE GREAT LAKES AND ADVECT COOLER AIR INTO THE CWA. HIGHS WILL  
RANGE FROM THE UPPER 50S NORTH TO LOWER 60S SOUTH. A SLOW WARMING  
TREND WILL SEND HIGHS INTO THE UPPER 60S BY TUESDAY.  
   
..WET THE LATTER HALF OF THE WEEK
 
 
THE ECMWF AND GFS HAVE BEEN SURPRISINGLY LOCKED INTO THE IDEA OF  
ANOTHER LOW MOVING OVER THE CWA WEDNESDAY. THIS LOW HAS A LOT OF GULF  
MOISTURE WITH IT AND IS FOLLOWED BY A SECOND LOW THURSDAY. THAT WILL  
KEEP RAIN IN THE FORECAST THROUGH FRIDAY. HIGHS WILL ALSO REMAIN IN  
THE 60S THROUGH FRIDAY BEFORE CLIMBING INTO THE 70S SATURDAY.  
 

 
   
AVIATION
 
(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)  
ISSUED AT 724 AM EDT SAT MAY 21 2022  
 
CURRENTLY WE HAVE MVFR/IFR CIGS NEAR THE FRONTAL SYSTEM OR NEAR  
AND SOUTH OF A LINE FROM LAN TO BTL, NORTH OF THAT IT IS VFR.  
THERE ARE CLUSTERS OF THUNDERSTORMS NEAR AND SOUTH OF THAT SAME  
LINE TOO. I AM EXPECTING THIS AREA OF SHOWERS TO PUSH OFF TO THE  
EAST AND WEAKEN BY LATE THIS MORNING. I SEEMS TO ME THE WAVE ON  
THE FRONT CAUSING THE CURRENT PRECIPITATION WILL BE OUT OF OUR  
AREA BY LATE MORNING. THIS SHOULD GIVE ALL OF OUR TAF SITES VFR  
CONDITIONS INTO LATE AFTERNOON. THEN THE NEXT AND FINAL WAVE ON  
THE FRONT MOVES THROUGH. THERE IS CONSIDERABLE QUESTION AS TO HOW  
FAR NORTH THE MVFR CIGS/VSBY GET THIS EVENING WITH THIS NEXT AND  
FINAL AREA OF SHOWERS IN ISOLATED THUNDERSTORMS. SKIES SHOULD  
CLEAR BY MID MORNING SUNDAY.  
 

 
   
MARINE
 
 
ISSUED AT 324 AM EDT SAT MAY 21 2022  
 
DRIER AIR BEHIND A COLD FRONT IS MOVING OVER THE LAKE AND SCOURING  
OUT THE FOG. AS SUCH, WE HAVE CANCELED THE DENSE FOG ADVISORY. WIND  
AND WAVES WILL REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA FOR THE  
NEXT SEVERAL DAYS.  
 

 
   
GRR WATCHES/WARNINGS/ADVISORIES
 
 
MI...NONE.  
LM...NONE.  

 
 

 
 
UPDATE...MEADE  
DISCUSSION...04  
AVIATION...WDM  
MARINE...04  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab MI Page
The Nexlab IN Page Main Text Page