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fxus63 kgrr 221737 
afdgrr

Area forecast discussion
National Weather Service Grand Rapids Michigan
1237 PM EST Fri Nov 22 2019

Latest update...
synopsis/aviation/marine

Synopsis...
issued at 1238 PM EST Fri Nov 22 2019

- skies will clear by evening / colder tonight

- pleasant weather this weekend / storm system misses SW Michigan to
south Saturday

- system passes north of area Monday brings warmer air into area

- a storm system with strong winds more than possible late Tuesday
into Wednesday. Precipitation type seems to favor mostly rain
but that is not a sure thing at this point.




&&

Update...
issued at 854 am EST Fri Nov 22 2019

I increased the cloud cover to nearly overcast through late
morning then allowed slow clearing this afternoon.

It would seem the cloud cover will be slower to leave the area
earlier through. Based on the mean relative humidity in the 950 mb to 850 mb
layer and looking at infrared and visible satellite loops and considering
the cold advection at low levels does not really come to an end
till early to mid afternoon, I would think the clouds will last
into mid afternoon. Skies should for the most part clear by late
afternoon.

&&

Discussion...(today through next thursday)
issued at 308 am EST Fri Nov 22 2019

Winds are slowly diminishing across the cwa early this morning.
Skies remain cloudy and the light rain has just about ended. The
cold front is moving across Lake Erie and high pressure will build
into the state today. We may actually see a little sunshine late
this afternoon that will continue during the daylight hours over the
weekend.

The next weather maker is low that will approach from the southwest
Tuesday. European model (ecmwf) ensembles suggest this will be another wind maker and
perhaps stronger than yesterday's storm. The Euro is a bit farther
west than the GFS and so places west Michigan in the warm sector and
pushes the snow over northern lower. The GFS is farther south and
would dump some snow over the cwa. The Canadian model leans toward
the Euro and so will we. Thus, we're looking at mainly rain Tuesday.
However over the northern cwa some wet snow could mix in. The pcpn
should diminish by Wednesday with high pressure building into the
Great Lakes on Thanksgiving.

&&

Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1238 PM EST Fri Nov 22 2019

I expect skies to become clear or nearly so by late this
afternoon. Currently MVFR cigs prevail over most of our taf sites
but visible satellite images show breaks in the clouds over
southwest Michigan and skies clear over most of Wisconsin. Since
the back edge of the polar jet will exit east of this area by mid
afternoon, that will allow more subsidence and that in turn will
clear the clouds. Also low to mid level warm advection will help
that cause too.

The surface high passing over southern Michigan tonight will allow
for clear skies and light winds. The next system will pass off to
the south of Michigan Saturday into Saturday night. The
precipitation should stay south of our County Warning Area but it would not be
impossible for jxn to get some sprinkles from a mid deck cloud
base in the evening. For the most part most of our taf sites
should see mostly clear to partly cloudy skies (mid clouds) from
the system passing to our south.




&&

Marine...
issued at 1238 PM EST Fri Nov 22 2019

I plan on dropping the Small Craft Advisory with the next forecast issuance during
the mid afternoon as none of our reporting sites have Small Craft Advisory criteria
at this point. The next Small Craft Advisory event is expected on Monday.




&&

GRR watches/warnings/advisories...
Michigan...none.
Lm...Small Craft Advisory until 4 PM EST this afternoon for
lmz844>849.

&&

$$

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