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Area forecast discussion...corrected 
National Weather Service Grand Rapids Michigan
330 PM EDT sun Apr 26 2015

Latest update...
synopsis/short term/long term/marine

issued at 330 PM EDT sun Apr 26 2015

A ridge of high pressure stretching from Hudson Bay to Minnesota
will move slowly east the next couple days. Dry weather will
continue although it will remain cool with periods of cloudiness.

Above normal temperatures are expected next weekend but rain chances
will increase.


Short term...(this evening through Tuesday night)
issued at 330 PM EDT sun Apr 26 2015

Several vorticity maxima pinwheeling around the western side of the
large upper low to our east will sling clouds in from the northeast
tonight and Monday. These clouds will be augmented by diurnal
cumulus formation during the afternoon hours due to a cold pocket
aloft... particularly east of Highway 131.

On Tuesday... the combination of shortwave ridging... slight warming
aloft... and closer proximity of the surface ridge should result in less
cloudiness than on Monday.

Frost potential is not particularly high tonight with surface winds
holding up at 5 to 10 kts and some clouds around... but will mention
some patchy frost. Frost potential looks better on Monday and
Tuesday nights due to lighter winds with the surface ridge building in.

Long term...(wednesday through sunday)
issued at 330 PM EDT sun Apr 26 2015

Temperatures will slowly climb into the 70s by the weekend. For the
most part...the long term will be dry. However the weekend may be

A digging short wave over the central Great Lakes will largely miss
SW lower Michigan Wednesday/Wednesday night except for the far eastern County Warning Area. Dry weather
is expected behind the trough for Thursday and Friday. A better
chance of rain exists Friday night and Saturday as a weak front
pushes through the County Warning Area. That weak cold front will return north
Sunday as a warm front. Southwest flow ahead of it will pull
moisture northward along with warmer temperatures. The combination
of those two will create some instability Sunday along the frontal
boundary. We added a slight chance of thunder to the grids Sunday as
both the GFS and European model (ecmwf) showed some cape with Li/S around -2c.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 136 PM EDT sun Apr 26 2015

Scattered cumulus will dissipate a bit toward sunset and the gusty
winds will diminish too. Low pressure over Ontario will push
stratocu southwestward toward the taf sites overnight and ceilings will likely
fall to around 1500 feet by 08-10z.


issued at 330 PM EDT sun Apr 26 2015

Marginal Small Craft Advisory conditions south of Whitehall through
middle evening with north-northwest winds 15-25 kts... but will let the advisory
ride for now. Similar conditions expected Monday afternoon/evening.


issued at 1059 am EDT sun Apr 26 2015

Rivers across southwest lower Michigan are mostly around normal
levels and steady or slowly falling. With dry weather forecast... no
changes are expected this week.


GRR watches/warnings/advisories...
Lm...Small Craft Advisory until 11 PM EDT this evening for



short term...Meade
long term...04

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