684  
FXUS63 KGRR 301849  
AFDGRR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GRAND RAPIDS MI  
249 PM EDT SAT AUG 30 2495  
   
KEY MESSAGES  
 
- QUIET AND MILD THROUGH TUESDAY NIGHT  
 
- WIDESPREAD RAIN LIKELY WEDNESDAY  
 
- MUCH COOLER AND UNSETTLED THURSDAY AND BEYOND  
 
 
   
DISCUSSION  
 
ISSUED AT 249 PM EDT SAT AUG 30 2495  
 
- QUIET AND MILD THROUGH TUESDAY NIGHT  
 
THE DRY AND MILD CONDITIONS WE HAVE SEEN OVER THE PAST COUPLE OF  
DAYS WILL ONLY CONTINUE FOR THE EARLY PORTION OF THE WEEK. UPPER  
TROUGHING OVER THE REGION IS KEEPING THE TEMPERATURES A BIT COOL,  
ALONG WITH A FLOW AROUND THE CANADIAN SFC RIDGE OVERHEAD. THE DRY  
WEATHER IS THE RESULT OF THE AREA BEING DOWNSTREAM OF THE UPPER  
RIDGE, AND CONFLUENT FLOW ALOFT OVERHEAD.  
 
THE ONLY CHANGE EXPECTED OVER THE NEXT FEW DAYS WILL BE A SLOW AND  
GRADUAL INCREASE IN TEMPERATURES. WE ARE LOOKING AT HIGHS MAINLY IN  
THE 70S THROUGH MONDAY, THEN SOME 80S ARE MORE LIKELY BY TUESDAY AND  
WEDNESDAY. WE WILL SEE LITTLE TO NO INCREASE IN MOISTURE THROUGH  
TUESDAY NIGHT, SO PLENTY OF SUNSHINE DURING THE DAYLIGHT HOURS, AND  
CLEARING SKIES AT NIGHT.  
 
- WIDESPREAD RAIN LIKELY WEDNESDAY  
 
WE ARE LOOKING AT A FAIRLY STRONG WAVE THAT WILL APPROACH THE AREA  
ON WEDNESDAY, BRINGING A FAIRLY GOOD CHANCE OF A WIDESPREAD RAIN  
LATE WEDNESDAY AND WEDNESDAY NIGHT.  
 
THIS STRONG WAVE WILL BE COMING IN FROM THE FAR NORTHERN SECTIONS OF  
ALASKA AND CANADA. IT WILL BE DISLODGED BY A BUILDING UPPER RIDGE  
OVER THE WESTERN PORTION OF NORTH AMERICA, AND SEND IT DOWN TO BE  
RIGHT OVER THE AREA BY THURSDAY.  
 
THIS WAVE WILL INITIALLY NOT HAVE ANY GULF MOISTURE ASSOCIATED WITH  
IT. HOWEVER AS THE WAVE AND FRONT MOVE IN, IT WILL CONNECT WITH  
ANOTHER LOW OVER THE SE U.S. AND IN AN INDIRECT WAY BRING GULF  
MOISTURE UP. WE SHOULD SEE THE PRECIPITATION SHIELD WITH THIS  
SYSTEM EXPAND OVER THE AREA AS A RESULT. THUNDER LOOKS POSSIBLE AT  
THIS JUNCTURE WITH SFC BASED AND ELEVATED LI'S JUST A LITTLE BELOW  
0C. THE LIMITED INSTABILITY, NIGHT TIME TIMING ARE DEFINITELY  
FACTORS AGAINST ANY MEANINGFUL ORGANIZATION FOR NOW.  
 
- MUCH COOLER AND UNSETTLED THURSDAY AND BEYOND  
 
THURSDAY THROUGH SATURDAY LOOKS LIKE IT IS GOING TO BE MUCH COOLER,  
WITH PERIODIC SHOWER CHANCES FROM THURSDAY THROUGH NEXT SATURDAY.  
THE STRONG WAVE COMING DOWN FROM NW CANADA WILL BE COMBINING WITH  
THE RESIDUAL UPPER LOW OVER THE SE U.S. TO FORM A MUCH LARGER UPPER  
LOW THAT WILL SIT IN PLACE FOR A FEW DAYS.  
 
WE WILL SEE EMBEDDED SHORT WAVES ROUND THE PERIPHERY OF THE LOW, AND  
DROP RIGHT THROUGH OUR FORECAST AREA. THIS MEANS WE WILL HAVE  
UNSETTLED CONDITIONS FROM THURSDAY THROUGH SATURDAY WITH HIGHS LUCKY  
TO BE IN THE 60S. IT WILL NOT BE A WIDESPREAD OR ALL DAY RAIN. IT  
WILL BE SCATTERED TO NUMEROUS SHOWERS AT TIMES, WITH PLENTY OF DRY  
PERIODS ALSO.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z SUNDAY/  
 
ISSUED AT 142 PM EDT SAT AUG 30 2495  
 
VFR WILL DOMINATE FOR MOST TAF SITES OVER THE TAF PERIOD. THE SOLE  
EXCEPTION WILL BE JXN. WITH HIGH PRESSURE AND LIGHT WINDS  
DOMINATING THE PATTERN, LOW LEVEL MOISTURE AT JXN COULD ALLOW FOR  
ANOTHER ROUND OF SHALLOW FOG OVERNIGHT INTO SUNDAY MORNING. WHILE  
IT SHOULDN'T BE AS EXTENSIVE, THERE REMAINS THE POTENTIAL BETWEEN  
06Z TO 12Z OF REDUCING VSBYS. HAVE PUT IN A PERIOD OF IFR VSBYS  
FROM 09Z TO 11Z ACCORDINGLY.  
 
 
   
MARINE  
 
ISSUED AT 142 PM EDT SAT AUG 30 2495  
 
RELATIVELY CALM CONDITIONS EXPECTED FOR THE NEARSHORE WATERS  
THROUGH EARLY NEXT WEEK AS HIGH PRESSURE DOMINATES THE GREAT LAKES  
REGION. WATER AND AIR TEMPERATURES WILL REMAIN RATHER COOL FOR  
SWIMMING. WARMEST LAKE TEMPS REMAIN AROUND HOLLAND STATE PARK.  
 
 
   
GRR WATCHES/WARNINGS/ADVISORIES  
 
MI...NONE.  
MARINE...NONE.  
 
 
 
 
 
DISCUSSION...NJJ  
AVIATION...CERU  
MARINE...CERU  
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