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fxus63 kgrr 231926 
afdgrr

Area forecast discussion
National Weather Service Grand Rapids Michigan
325 PM EDT Fri Aug 23 2019

Latest update...
synopsis/discussion/marine

Synopsis...
issued at 325 PM EDT Fri Aug 23 2019

- dry and mild through Sunday

- rain chances Monday through Tuesday

- comfortable weather holds for next week

&&

Discussion...(this evening through next friday)
issued at 325 PM EDT Fri Aug 23 2019

We have at least one period of weather from Monday into Tuesday that
will have some impacts. There will potentially be another period of
some weather late in the period, but that is a bit uncertain for now.

Through early Monday, the weather is looking quite comfortable and
quiet. The upper trough that has lingered over the area the last
couple of days will exit to the east. This will allow the upper
ridge axis to slowly build over the region. Cumulus cloud
development will diminish a bit with the subsidence building in. We
will also slowly warm a couple of degrees each day.

The chance of rain will increase on Monday, and likely peak Monday
night. A short wave to our SW will be pushed to the NE as a larger
amplitude short wave arrives from the west. This initial short wave
will help bring decent moisture up and over the area. Then, the
stronger short wave with the better dynamics will interact with the
moisture to bring good chances of rain. The timing as of now does
not look conducive for a lot of severe weather.

The front should clear out then on Tuesday after some residual early
showers and storms with the frontal passage. It looks like we should
end up with some cooler and drier weather. The Heart of the cold
pool aloft stays north, keeping instability clouds and showers
north.

We will be likely seeing another short wave arriving into the region
in the Thu or Fri time frame. The timing is uncertain, so we have
small chances for that whole period. The rain chances can be fine
tuned with plenty of time before then.

&&

Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 126 PM EDT Fri Aug 23 2019

Impacts look like they will be little to non for aviation
interests for the next 24 hours. Cumulus development will be sct-
bkn this afternoon, but will be all VFR with bases above 4k ft.
These clouds should be quick to dissipate this evening with the
loss of diurnal heating, leaving clearing skies and light east/NE
winds. Can not rule out some shallow ground fog near warmer bodies
of water. The dry air in place should keep fog away from the
terminals.

We expect another round of cumulus development for Saturday
afternoon also. This will again be VFR, and will have little to no
impacts. East/NE winds are once again expected.



&&

Marine...
issued at 325 PM EDT Fri Aug 23 2019

No marine headlines expected to be needed through much of this
weekend. Winds maybe up around 15 knots during the daylight hours
with Land/Lake interactions, but not high enough through early
Sunday for headlines.

Winds will start to increase late Sunday with the approach of the
next system. Once the winds increase late Sunday, winds may remain
up for the most part through mid week, with headlines likely then.

&&

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

$$

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