602  
FXUS63 KGRR 262350  
AFDGRR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GRAND RAPIDS MI  
750 PM EDT TUE MAY 26 2020  
 
LATEST UPDATE...  
AVIATION  
   
SYNOPSIS
 
 
ISSUED AT 300 PM EDT TUE MAY 26 2020  
 
- ISOLATED SHOWERS/STORMS TODAY/WEDNESDAY  
 
- NUMEROUS SHOWERS/THUNDERSTORMS WITH THE FRONT THURSDAY  
 
- SUMMER-LIKE TEMPERATURES TODAY/WEDNESDAY, COOLER BY THE WEEKEND  
 

 
   
DISCUSSION
 
(THIS EVENING THROUGH NEXT TUESDAY)  
ISSUED AT 204 PM EDT TUE MAY 26 2020  
 
- ISOLATED SHOWERS/STORMS TODAY/WEDNESDAY  
 
DIURNALLY DRIVEN SCATTERED CONVECTION WILL CONTINUE THROUGH THE  
EARLY EVENING HOURS. THESE STORMS AND SHOWERS WILL END SHORTLY  
AFTER SUNSET. THE BIGGEST CONCERNS WITH THESE STORMS  
 
TOMORROW THE REGION WILL BE IN THE SAME AIR MASS. THE MAIN  
CONCERN WILL BE CONVECTION FORMING TOMORROW AFTERNOON ALONG THE  
LAKE BREEZE. DAYTIME TEMPEATURES TOMORROW WILL AGAIN BE IN THE  
80S.  
 
- NUMEROUS SHOWERS/THUNDERSTORMS WITH THE FRONT THURSDAY  
 
THE GREAT LAKES REGION WILL BE TRAPPED BETWEEN TWO SYSTEMS  
WEDNESDAY INTO THURSDAY. A LARGE UPPER LEVEL LOW WILL BE MOVING  
THROUGH THE SOUTH AS HIGH PRESSURE IS PUSHED INTO THE NORTHERN  
ATLANTIC. A FAIRLY TIGHT GRADIENT SHOULD FORM BETWEEN THOSE  
SYSTEMS AND A DEEPENING UPPER LEVEL TROUGH THAT WILL BE MOVING  
SOUTHERN CANADA AND INTO THE REGION. MOISTURE WILL STREAM INTO THE  
REGION BETWEEN THESE SYSTEMS, THAT COUPLED WITH THE GRADIENT  
SHOULD ALLOW FOR MORE WIDESPREAD CONVECTION THURSDAY. THE LATEST  
ENSEMBLES HAVE +2 ANOMALOUS PWATS ASSOCIATED WITH THIS SYSTEM.  
COUPLE THAT WITH THE WARM AIR AHEAD OF IT AND THERE ARE ALL THE  
INGREDIENTS FOR DECENT STORMS. THERE IS STILL SOME QUESTION HOW  
FAST THE SYSTEM MOVES THROUGH, WHERE IT COULD STALL THURSDAY NIGHT  
INTO FRIDAY.  
 
IT WILL THEN MAKE ITS WAY EASTWARD WITH DRY COLD AIR FILTERING  
INTO THE REGION SATURDAY INTO SUNDAY.  
 
- SUMMER-LIKE TEMPERATURES TODAY/WEDNESDAY, COLD TEMPS THIS  
WEEKEND  
 
THE TEMPERATURE TREND THIS WEEK IS WARMER THEN NORMAL TEMPERATURES  
TODAY AND TOMORROW. MUSKEGON HAS ALREADY BROKEN THE RECORD HIGH  
TEMPERATURE FOR THE DAY AND IT IS POSSIBLE TO BREAK RECORDS  
ELSEWHERE. WEDNESDAY WILL BE WARM AS WELL, THOUGH CURRENT MODEL  
TRENDS SHOW IT SLIGHTLY COOLER.  
FRONTAL PASSAGE ON THURSDAY WILL PUT A KIBOSH ON THE WARMER  
TEMPERATURES FOR THIS WEEK. A DRIER, COLDER AIR MASS WILL DROP  
INTO THE AREA BY SATURDAY. THIS WILL DROP MAX TEMPERATURES TO  
BELOW NORMAL. THE BIGGEST CONCERN FOR THIS WEEKEND WILL BE MINIMUM  
TEMPERATURES SATURDAY NIGHT INTO SUNDAY. THERE IS A GOOD SIGNAL  
FOR TEMPS IN THE MID 30S NORTH OF EVART AND REED CITY. SO WILL  
NEED TO KEEP AN EYE ON POSSIBLE FROST POTENTIAL SUNDAY MORNING.  
 

 
   
AVIATION
 
(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)  
ISSUED AT 750 PM EDT TUE MAY 26 2020  
 
SHOWERS AND THUNDERSTORMS WILL BE DECREASING THIS EVENING WITH  
VFR CONDITIONS PREVAILING THROUGH 12Z WEDNESDAY. SOME ISOLATED IFR  
IS POSSIBLE WEDNESDAY AFTER 15Z AS SHOWERS POP UP AGAIN.  
 

 
   
MARINE
 
 
ISSUED AT 310 AM EDT TUE MAY 26 2020  
 
WIND AND WAVES WILL NOT POSE A THREAT TO BOATERS TODAY OR WEDNESDAY.  
 

 
   
HYDROLOGY
 
 
ISSUED AT 1115 AM EDT TUE MAY 26 2020  
 
THE GRAND RIVER AT COMSTOCK PARK AND ROBINSON TOWNSHIP ARE  
CONTINUING TO FALL BUT WILL REMAIN ABOVE FLOOD STAGE AT LEAST  
THROUGH WEDNESDAY.  
 
THE LACK OF BASIN-WIDE RAINFALL THE LAST FEW DAYS IS CONTRIBUTING TO  
A STEADY FALL ON AREA STREAMS AND RIVERS. MORE SUBSTANTIAL RAINFALL  
IS POSSIBLE THURSDAY AS A COLD FRONT MOVE THROUGH THE AREA. RUNOFF  
FROM THAT RAINFALL MAY SLOW THE RATE OF FALL OF SOME RIVERS.  
 

 
   
CLIMATE
 
 
ISSUED AT 750 PM EDT TUE MAY 26 2020  
 
RECORD WARMEST LOWS FOR MAY 27:  
GRR 69 (1987)  
LAN 70 (1908)  
MKG 67 (1987)  
AZO 70 (1941)  
 
RECORD HIGHS MAY 27  
GRR 93 (2018)  
LAN 93 (1911)  
MKG 87 (2018)  
AZO 94 (2012)  
 
RECORD LOWS MAY 31  
GRR 36 (1966)  
LAN 32 (1966)  
MKG 35 (1910)  
AZO 36 (1889, 1897)  
 

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

 
 

 
 
SYNOPSIS...CERU  
DISCUSSION...CERU  
AVIATION...OSTUNO  
MARINE...04  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab MI Page
The Nexlab IN Page Main Text Page