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fxus63 kgrr 251118 

Area forecast discussion
National Weather Service Grand Rapids Michigan
718 am EDT sun Aug 25 2019

Latest update...

issued at 223 am EDT sun Aug 25 2019

- one more day of fair weather

- showers and a few thunderstorms move in Monday


Discussion...(today through next saturday)
issued at 223 am EDT sun Aug 25 2019

Sfc high will provide one more day of fair weather and then
moisture begins to return as it moves east tonight and Monday.
Moisture advection and isentropic ascent increases on Monday with
scattered showers breaking out during the morning and increasing
into the afternoon.

A sfc low tracking north of Lake Superior will bring a trailing
cold front through late Monday night. Thunderstorms are expected
along the front but coverage and strength will be mitigated by
marginal instability during late night passage. Precipitable water
values are approaching 1.9 inches overnight so heavy rain rates
are expected with any deep convection, and any area that sees
training of storms in southerly flow could get some localized
flooding late Monday night into early Tuesday morning.

Another period of fair and cool weather to follow for Wednesday
through Saturday as Canadian high pressure returns and persists
across the central Great Lakes.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 718 am EDT sun Aug 25 2019

VFR conditions will continue through tonight. Winds will be east
around 5 to 10 knots.


issued at 223 am EDT sun Aug 25 2019

South winds will be on the increase today and waves will begin to
build through Monday. A Small Craft Advisory will likely be needed
north of Holland from Monday afternoon into Tuesday afternoon.


GRR watches/warnings/advisories...


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