734 
FXUS63 KGRR 061812
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
112 PM EST Sun Nov 6 2022

LATEST UPDATE...
Aviation

.DISCUSSION...(Today through next Saturday)
Issued at 245 AM EST Sun Nov 6 2022

- Breezy Today; Tranquil Weather into Mid Week

One more day with gusty winds to get through, but not as bad as 
Saturday. After a reprieve in the wind gusts into early morning, 
there will be a resurgence in 925mb winds of 30-40 kts during the 
late morning into afternoon, which Bufkit mixing heights reveal we 
should be able to tap. The highest gusts will likely be along the 
lakeshore north of MKG where some sfc gusts could reach the 35-40 kt 
(over 40 mph) at times. Most inland locations should have gusts in 
the 30-40 mph range, so that is lower than Saturday for sure but 
still breezy. Winds will greatly tail off toward sunset and beyond. 
Monday looks much less breezy with 10-20 mph expected.

There is good model agreement on dry conditions, seasonable 
temperatures, and a fair amount of sun for Monday and Tuesday as 
upper ridging dominates the Great Lakes during that time. Low level 
warm air advection increases markedly for Wednesday and Thursday 
with 850mb temperatures rising into the 12C-15C range. With deep 
southwest synoptic scale flow in place by Thursday, we should be 
able to mix down dry adiabatically from about 900mb and boost highs 
back to around 70 away from the lake. Aside from something 
climatologically extreme happening later this month, that should be 
the last day we'll reach 70 anywhere for quite some time.

- Turning Breezy Again Late Week, With Some Rain Showers

An upper low approaching the Pacific NW at this time is slated to 
move into the Upper Midwest by late in the week. Given its 
trajectory over the Rockies midweek, lee cyclogenesis is forecast by 
medium range guidance and a deepening low is expected to move toward 
Minnesota by Thursday before occluding. This type of storm track 
would not give our region significant rainfall, but it would get us 
into the warm sector and provide a period of gusty winds especially 
Thursday into Friday. A cold front will probably sweep through the 
state sometime Friday afternoon or evening. Even five days out, 
forecast confidence is pretty good on FROPA timing.

- Colder Air and Lake Effect Snow Showers Arrive This Weekend

There is really little doubt that cold air advection behind this 
front will be sufficient enough for lake effect snow shower 
generation Saturday into Sunday. GFS ensemble spread on 850mb 
temperatures is not large when looking at the 25th-75th percentiles 
this coming weekend. At least at this long range, low level moisture 
looks pretty solid off the GFS/ECMWF/GEM, so the main question may 
be wind direction which is certainly in flux this far out. A general 
transition from W/WNW/NW flow is the early indication over the 
course of the weekend. Some accumulating snow is favored by most 
ensemble members for various locations mainly near and west of US
131, but this is too far out to talk specifics and precise 
locations. That said, this coming weekend will be the first time 
this season that any sort of travel impacts could potentially 
occur due to winter weather. The ensemble guidance favors 
temperatures to be below normal starting this upcoming weekend and
likely several days beyond that. This would equate to highs 
mainly in the 30s for many locations. 

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 112 PM EST Sun Nov 6 2022

Main concern aviation wise the next 24 hour will be the wind for
the remainder of the afternoon. South to southwest winds of 15-30
knots will be common for the remainder of the afternoon. We should
see winds settle after 22z-23z into more of a 10-20 knot range.
MKG may continue to be gustier all night though given its
proximity to Lake Michigan with a wind off the lake. 

Otherwise, we are expecting mainly clear skies through the TAF
period with no restrictions to visibility.

&&

.MARINE...
Issued at 245 AM EST Sun Nov 6 2022

High wave action persists today with renewed wind gusts hovering
near gales. These higher winds will subside toward dark, but a
northwesterly wind shift on Monday will keep elevated waves of 3
to 6 ft going even as winds subside below 25 kts during the
afternoon.


&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...Small Craft Advisory until 1 PM EST Monday for LMZ844>847.

     Gale Warning until 7 PM EST this evening for LMZ848-849.

     Small Craft Advisory from 7 PM this evening to 1 PM EST Monday 
     for LMZ848-849.

&&

$$

DISCUSSION...Hoving
AVIATION...Duke
MARINE...Hoving