FXUS63 KGRR 230825

Area Forecast Discussion
National Weather Service Grand Rapids MI
325 AM EST Thu Nov 23 2017

Synopsis/Short Term/Long Term/Marine

Issued at 325 AM EST Thu Nov 23 2017

A lengthy stretch of relatively benign weather is expected
through the end of the month with above normal temperatures and
very little precipitation. A weak cold front will bring a few
scattered light rain showers on Friday night and Saturday
otherwise dry weather is in store the next several days.


.SHORT TERM...(Today through Saturday)
Issued at 325 AM EST Thu Nov 23 2017

Weak isentropic lift early this morning is leading to an overcast mid
level cloud deck and some weak echoes aloft. This is mainly a
virga event this morning, followed by decreasing clouds from west
to east this afternoon with the passage of the warm front.

Have nudged up high temps a bit for Friday with strong southerly
flow in warm sector. Most locations should get into the lower 50s
and possibly even mid 50s, although the breezy conditions will
make it feel cooler.

Guidance showing only paltry rain amounts of less than a tenth of
an inch with the cold frontal passage on Friday night, primarily
north of I-96. Lake effect potential looks quite low behind the
front on Saturday due to shallow moisture and mild boundary layer
temps. Only chance pops are warranted Saturday north of I-96,
with the main threat of a few rain or mixed rain and snow showers
near and north of Highway U.S. 10.

.LONG TERM...(Saturday night through Wednesday)
Issued at 325 AM EST Thu Nov 23 2017

Much of the long term looks to be quiet with above average
temperatures. The one period that could be a bit unsettled will be
from Tue night into Thu.

Pcpn that will be possible at the end of the short term should come
to an end by the long term, which starts on Sat night. The upper
trough that will be over the area at the end of the short term will
be east of the CWFA by Sun morning with sfc ridging also building in.

We will see a nice push of warm air make it's way toward the area
for Mon and Tue. This will come via fairly decent SW winds between
the departing high, and incoming sfc low. We should see a decent
amount of sunshine Mon and Tue as the flow is not really tapping
much Gulf moisture.

Things become a bit uncertain from Tue night and beyond. There is
good agreement we will see a front push through first late Tue. This
will usher in cooler air, but not have much pcpn with it with a lack
of a moist flow. The uncertainty comes as there looks to be
additional energy to our SW that could interact with the front at
some point, and another nrn wave diving SE. The interaction of all
of these features will ultimately determine when and how much pcpn
occurs. The trend has been for a quicker initial frontal passage,
and less pcpn as everything will be focused further South.


.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1255 AM EST Thu Nov 23 2017

This fcst period looks to be rather benign for the SW Michigan
terminals. We currently have mid cloud cover moving overhead,
based around 6-10k ft. This will remain the case for most of the
day before the clouds move out late this afternoon.

We will see winds pick up after sunrise when better mixing begins.
Wind gusts up around 20 kts will be likely through the daylight
hours, before diminishing toward sunset.


Issued at 325 AM EST Thu Nov 23 2017

Southwest flow is increasing early this morning and Small Craft
Advisory will be in effect today. The gradient relaxes tonight but
tightens again considerably on Friday in the warm sector. Gale
Watch for Friday looks good, although have delayed it slightly
from earlier issuance with a start time now of 7 AM Friday.


Issued at 308 PM EST Wed Nov 22 2017

A few river flood advisories remain in effect but water levels
will slowly fall through the rest of the week and weekend as
no significant precipitation is forecast through the weekend into
early next week.


LM...Gale Watch from Friday morning through Friday evening for

Small Craft Advisory until 5 PM EST this afternoon for



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