Weather

868 
fxus63 kgrr 290804 
afdgrr 


Area forecast discussion 
National Weather Service Grand Rapids Michigan 
405 am EDT Friday Aug 30 2008 


Latest update...all but aviation... 


Synopsis...(405 am EDT Friday Aug 30 2008) 
a cold front moving across Lake Michigan will generate a few showers 
early this morning before high pressure moves in and produces 
sunshine for much of the day. Dry weather is expected for the Labor 
Day weekend with high temperatures well above average. 


&& 


Short term...(405 am EDT Friday Aug 30 2008) 
forecast concerns today deal with precipitation trends this morning. Surface 
analysis shows a weak cold front moving across Lake Michigan at this time. Scattered 
showers are developing ahead of the front. Not seeing much thunder 
at this time as instability is weak...and not expected to get much stronger. 
The front is moving a little slower than anticipated and so we/ll 
have to keep precipitation in the grids into the morning. Infrared loop shows clear 
skies on the west side of the lake with quite a bit of debris clouds 
over Michigan from the mesoscale convective system to the south. Skies will become mostly 
sunny later today after the front moves east and the debris clouds 
dissipate. Dry and warm weather then expected through the weekend. 


&& 


Long term...(405 am EDT Friday Aug 30 2008) 
(sunday night through thursday) 
high amplitude upper ridge will likely be slow to break down so 
prospects for rain do not look good for the middle to late week period. 
The GFS is still trying to send a front into the region Wednesday night... 
but it will probably be delayed or perhaps completely dissolve 
before reaching lower Michigan. Will maintain chance probability of precipitation for Wednesday 
night and Thursday but confidence in a rain event are currently very 
low. In fact the hot/dry pattern looks to persist through 07sep per 
latest GFS and European model (ecmwf). 


&& 


Marine...(405 am EDT Friday Aug 30 2008) 
high pressure will move in behind the cold front. The gradient 
behind the front isn/T all that strong and neither is the cold air 
push. As a result...winds and waves will remain below Small Craft Advisory criteria. 


&& 


Aviation...(1148 PM EDT Thursday Aug 28 2008) 
the combination of light winds and high relative humidity values 
have created some increasing fog and haze as of midnight. Some IFR 
conditions are likely mainly for kazo kbtl and kjxn by 09z. We will 
need to monitor other taf sites closely. The convection crossing 
Lake Michigan is forecast to weaken as it tries to move into 
Michigan after midnight. I did keep the cumulonimbus wording in some of the 
tafs. Drying is forecast for Friday with conditions improving to 
VFR by noon. 


&& 


Hydrology...(405 am EDT Friday Aug 30 2008) 
showers early this morning will generally produce less than a tenth 
of an inch of rain before moving east of the County Warning Area. Dry weather 
through the weekend will result in no Hydro concerns. 


&& 


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


&& 


$$ 


Synopsis: 93 
short term: 93 
long term: Meade 
marine: 93 
aviation: mjs 
hydrology: 93