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FXUS63 KGRR 181036

Area Forecast Discussion
National Weather Service Grand Rapids MI
636 AM EDT Wed Oct 18 2017


Issued at 313 AM EDT Wed Oct 18 2017

A large area of high pressure over the Central Appalachians will
dominate our weather pattern over the next few days. This system
will act to keep our weather dry with relatively warm and
breezy conditions continuing. A weakening cold front moves in 
from the northwest...but this system dissipates over the area on 


.SHORT TERM...(Today through Friday)
Issued at 313 AM EDT Wed Oct 18 2017

Models are in decent agreement in showing the cold front currently
in the Upper MS Valley to track southeast today and into the
region tonight. It will be weakening as it moves in and should
dissipate over the area on Thursday. The Gulf is cut off and this
feature will be lacking moisture. Thus no rain is in the forecast.
What cloud cover is associated with this front is mainly mid to
upper level cloudiness. 

Warm condition will prevail today a the low level thermal ridge
moves in. Based on the 925 temperature values...some 70s look
possible. Deeper mixing today will also support gusty wind
conditions. With mixing heights reaching into the 20 to 30 knot
winds...windy conditions look likely...especially the warmest part
of the day.

Less wind is forecasted for Thursday. The pressure gradient 
weakens as a result of the front dissipating over the area. Warm 
air advection resumes for Friday. Well above normal temperatures
will continue.

.LONG TERM...(Friday night through Tuesday)
Issued at 313 AM EDT Wed Oct 18 2017

Some changes are coming to the forecast, especially late in the 

High pressure over the southeast US will continue to bring warm air 
north through early Sunday. Highs in the 70s are expected Saturday 
and upper 60s Sunday. But then a cold front front blows through 
Sunday and models continue to show showers along the front. A very 
strong short wave coming in behind the front will then begin to 
carve out a very high amplitude trough over the Great Lakes early 
next week. We're likely to see the coldest air of the season so far 
during this time. H8 temps are progd to fall from 10c Tuesday 
morning to -4c by Wednesday morning. Highs Monday will be in the 
lower 60s, which will be much cooler than current temps, but still a 
couple of degrees above normal. By Tuesday, highs will only be in 
the lower to mid 50s. Given the strength of the short wave coming in 
next week, showers are likely during this time. 


.AVIATION...(For the 12Z TAFS through 12Z Thursday morning)
Issued at 634 AM EDT Wed Oct 18 2017

The atmosphere will remain relatively dry through the
period...especially in the low levels. Thus the forecast is for
VFR conditions at the TAF sites. A tight pressure gradient will
exist today. As the temperature warms up...this will increase the
mixing height...supporting increasing winds. It looks like gusts
over 20 knots will occur today.


Issued at 313 AM EDT Wed Oct 18 2017

The pressure gradient tightens up today as a cold front approaches
from the northwest. Ongoing small craft conditions will continue
for most of the region...but gales may develop this afternoon for
the northern couple of zones. The pressure gradient weakens later any gale conditions should diminish under criteria.


Issued at 305 PM EDT Tue Oct 17 2017

Most of the area rivers have reached their peak from the heavy 
rainfall event over the weekend.  The exception is the Kalamazoo 
River at New Richmond...which should reach its crest early 
Wednesday before returning below bankfull stage early Thursday. 

High pressure will continue to dominate the area weather through 
Wednesday...with a dry frontal passage expected Thursday.  The next 
significant rain event is not expected until later Saturday into 
Sunday...when a stronger frontal system moves through the region.
The dry weather will allow area rivers to return to typical flows
for late October.


LM...Small Craft Advisory until 2 PM EDT this afternoon for LMZ848-

     Gale Warning from 2 PM this afternoon to 4 AM EDT Thursday for 

     Small Craft Advisory until 4 AM EDT Thursday for LMZ844>847.




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