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afdgrr

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

Latest update...
aviation

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 00z tafs through 00z sunday)
issued at 706 PM EDT Fri Aug 23 2019

I expect VFR conditions to prevail through the weekend into
Monday morning. The subsidence inversion will remain near 5,000 ft
so each afternoon for Saturday and Sunday we will have cumulus
clouds with bases near 5000 ft (start out with bases near 3500 ft
mid morning and by late afternoon bases will be 6000 ft. ) Skies
will clear both tonight and tomorrow night after the sun sets.
Winds will remain from the easts northeast into Sunday at the
surface.




&&

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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