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000 
FXUS63 KGRR 211852
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
252 PM EDT Mon Oct 21 2019

LATEST UPDATE...
Synopsis/Discussion/Marine

.SYNOPSIS...
Issued at 252 PM EDT Mon Oct 21 2019

- Winds gusting over 50 mph at times into this evening.

- Big waves on Lake Michigan through Tuesday night with coastal
  flooding and beach erosion.

- Colder weather from Wednesday into early next week.

&&

.DISCUSSION...(This evening through next Monday)
Issued at 252 PM EDT Mon Oct 21 2019

We will be watching a narrow line of convection currently in 
northern Illinois/southern Wisconsin move across Lake Michigan and
through southwest Lower Michigan this evening. Although this line
will probably be too low topped to produce much lightning, it 
could be able to being down some damaging winds. We have issued an
SPS for the strong wind gusts but will have to monitor closely for
the potential of severe criteria winds as the line moves through.

Coastal flooding and beach erosion expected Tuesday and Tuesday
night. Wind gusts over 50 mph are possible into this evening as
narrow line of convection is expected to move across the forecast
area. The LOT and GRR radar-derived wind profiles show a strong
low level core of high winds of 40 to 60 mph below 5000 feet AGL.
Some of these winds have been able to mix down this afternoon with
a few gusts over 50 mph.

Conditions will improve as the sfc low occludes and fills 
Wednesday. Cold air wraps in behind the low with some wet
snowflakes possible late Thursday night. Fair weather expected for
Friday and Saturday then a chance of showers Saturday night and 
Sunday as a surface low tracking north of the Great Lakes brings 
a trailing cold front through.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 147 PM EDT Mon Oct 21 2019

MVFR with periods of IFR conditions are expected through this 
evening in heavier downpours then IFR later tonight as the rain
moves east. Strong southeast winds with gusts to 45 knots are
possible through the evening. Thunder was left out of the forecast
but an isolated lightning strike is possible.

Winds will go southwest and continue to gust over 40 knots at 
times through Tuesday afternoon.

&&

.MARINE...
Issued at 252 PM EDT Mon Oct 21 2019

No changes to the Gale Warning. Core of high winds with gusts 
reaching 40 knot gales this afternoon is moving east so winds 
should actually decrease next few hours. Winds will go southwest
tonight and increase again on Tuesday. Gales to 35 knots will 
continue into Tuesday night before decreasing on Wednesday. 

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Lakeshore Flood Warning from 8 PM this evening to 8 AM EDT 
     Wednesday for MIZ037-043-050-056-064-071.

LM...Gale Warning until 8 AM EDT Wednesday for LMZ844>849.

&&

$$

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