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Area forecast discussion 
National Weather Service Grand Rapids Michigan 
721 am EDT Sat Jul 5 2008 


Latest update...aviation... 


Synopsis...(336 am EDT Sat Jul 5 2008) 
high pressure overhead will produce lots of sunshine today. A cold 
front will approach Monday night and bring the next chance of 
showers and thunderstorms. 


&& 


Short term...(336 am EDT Sat Jul 5 2008) 
(today through monday) 
forecast concerns are minimal today but deal with convective 
potential late Monday. 


High pressure overhead will mean lots of sunshine today and 
relatively light winds. Dewpoints will remain in the comfortable 
50s. More humid weather will begin to show up late tonight and 
Sunday as the high drifts east and south flow develops. Aloft...a 
more zonal flow pattern will develop Sunday that will allow short 
waves to move through the state. A cold front will also move 
southeast into the up Monday. The GFS shows a short wave moving 
through the County Warning Area Monday afternoon. The European model (ecmwf) is a bit farther south 
with it. Instability will be high Monday with Li/S near -6c. So will 
moisture. Precipitable waters  over 2 inches are forecasted Monday afternoon. Storms 
that develop could be heavy rain producers. At this time shear 
values are very low Monday...storm organization doesn/T look great. 
So we/ll run with a dry forecast until late Sunday night over the far northwest 
and then across the entire County Warning Area Monday. 


&& 


Long term...(336 am EDT Sat Jul 5 2008) 
(monday night through friday) 
shortwave trough passing across the Great Lakes region Monday night 
and Tuesday should bring a round of showers and thunderstorms with 
surface cold front moving through late Tuesday into Tuesday night. Dry 
weather expected on Wednesday through Friday with surface ridging in 
control. 


&& 


Marine...(336 am EDT Sat Jul 5 2008) 
no marine concerns today with the high overhead. Expect onshore 
winds to develop this afternoon. Waves will generally be a foot or 
less today and tonight. 


&& 


Aviation...(721 am EDT Sat Jul 5 2008) 
light winds and VFR today. Some light fog this morning will be gone 
by 14z. May see some light fog again late tonight primarily at jxn. 


&& 


Hydrology...(336 am EDT Sat Jul 5 2008) 
some area rivers are running a bit high due to recent heavy rains. 
But dry weather the next couple of days will allow them to fall. The next 
chance of significant rain arrives Monday night. 


&& 


GRR watches/warnings/advisories... 
Michigan...none. 
Lm...none. 


&& 


$$ 


Synopsis: 93 
short term: 93 
long term: ostuno 
marine: 93 
aviation: ostuno 
hydrology: 93