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fxus63 kgrr 120239 
afdgrr

Area forecast discussion
National Weather Service Grand Rapids Michigan
939 PM EST Mon Nov 11 2019

Latest update...
update

Synopsis...
issued at 330 PM EST Mon Nov 11 2019

-widespread snow south and east of Grand Rapids ending from
northwest to southeast this afternoon and early evening.

-Localized but intense lake effect snow impacting the Lake
Michigan shoreline tonight into Tuesday around South Haven and
Ludington

-over one foot of new snow possible between Holland and Benton
Harbor, including I-196 and where I-94 meets I-196

-additional light snow Wednesday afternoon and night; then dry
through next weekend

-record or near record cold through Wednesday, moderating above
freezing for the end of the week.

&&

Update...
issued at 929 PM EST Mon Nov 11 2019

I decided to add lake...Muskegon and Ottawa counties to the Winter
Weather Advisory. Bands of lake effect snow were on the increase
across these counties. New guidance indicates that some of these
bands will become locally intense and capable of several inches of
snow in several hours. This risk continues right through the
morning commute and possibly the afternoon. Thus with multiple
highways/routes through these regions impacted travel looks
likely. We will need to monitor Kalamazoo County as western parts
of the County are at an increase risk for impacts. Not all
guidance bring the heavier bands into the County.

I did add to the hazardous weather outlook a risk for impacts from
the system that moves in Wednesday afternoon into the night. This
looks like a south to southwest flow event with lake moisture
enhancing the fast moving system which moves in. Guidance has been
increasing the snowfall with this one...along with the winds to it
is looking increasingly likely that we may see some impacts. Right
now the area from Muskegon north to Ludington is forecasted to see
the most snow and wind.

&&

Discussion...(this evening through next monday)
issued at 330 PM EST Mon Nov 11 2019

Will probably remove a few counties from the winter wx advisory
on the northwest edge of the departing area of snow with this
update. Otherwise the current expiration of 7 PM looks good and
jxn will be the last to see the snow end around that time. Have
had several reports around 6 inches, and locations some could
reach 8-9" around jxn. Yet another right entrance region jet/mid
level fgen event that over-performed.

Based on the hi res guidance/href probability matched mean quantitative precipitation forecast
showing over one inch of water equivalent from the lake effect
snow band that hits far SW lwr Michigan tonight, have decided to bump
Van Buren and Allegan counties into a warning alongside the
counties which the iwx office already has in a warning. Fcst
soundings from the hrrr and NAM 3km at South Haven have deep
inversion heights to 10,000 ft or more and the lift in the dgz is
about as impressive as it gets.

Strong potential for snow rates of 2 inches or more per hour and
whiteouts tonight into early Tuesday could lead to some serious
travel impacts along I-196 south of Holland and I-94 west of
Kalamazoo. Temperatures falling to around 20 in this area should
result in slick roads and with the extreme snowfall rates we could
end up with multi-car pileups and lengthy traffic stoppages in
that heavily traveled area of SW lwr Michigan. The event should be
peaking during the Tuesday morning commute.

Meanwhile the intense north-S oriented band currently stretching down
the length of the entire lake still remains just offshore of
Ludington but will be moving onshore soon. Winds have become north-northwest
and Frankfort currently has a 1/4 mile vsby. Hi res guidance not
showing quite as much qpf in this area as south of Holland tonight
and tues, but still would not rule out some localized amounts
near one foot, especially with guidance suggesting the possibility
of a meso-low sliding south down the shoreline early Tuesday.
Will keep Mason and Oceana counties in an advisory but have
extended it through 5 PM Tuesday (warning south of Holland will
go through 5 PM as well).

Weakening trend in the lake effect develops later Tuesday and
especially on Tuesday night as the sfc ridge arrives. Another
burst of snow, with SW flow lake enhancement, arrives Wednesday
afternoon. Accums with this probably an inch or less south and
east of GRR but potential for 2-4" along the coast north of Grand
Haven. Much quieter weather and milder temps expected for
Thursday and beyond.

&&

Aviation...(for the 00z tafs through 00z Tuesday evening)
issued at 625 PM EST Mon Nov 11 2019

The main area of snow that led to impacts across the area was
pulling east of kjxn. However one more band was try to develop
between klan and kgrr. This should pull east over the next couple
of hours and could lead to a temporary reduction in the ceilings
and visibilities for some of the sites this Evening.

Lake effect snow bands will be moving onshore through the night
and into Wednesday. It looks likely that impacts will occur
generally along and west of a kgrr to kbtl line. Initially the
impacts will be seen at kmkg...then further inland into Tuesday as
the winds shift slightly. IFR looks likely with brief reductions
to LIFR a possibility especially closer to the Lakeshore.



&&

Marine...
issued at 330 PM EST Mon Nov 11 2019

No changes to the going marine headlines. Small craft advisories in
effect through Tuesday night for the strong northerly flow which
becomes northwest for Tuesday. Freezing spray may develop tonight
as the colder Arctic air pours in. Lakeshore flood advisory
continues for Allegan and Van Buren counties beach and Bluff
erosion is expected, as well as Lakeshore flooding in low lying
areas and along river mouths.



&&

Climate...
issued at 330 PM EST Mon Nov 11 2019

The current forecast of high temperatures in the mid 20s on
Tuesday would break the daily record for coldest highs (or lowest
maximum temperature). The low temperature forecast for Tuesday and
Wednesday would come within a few degrees of breaking daily
records at some locations.

Record coldest high temperatures for November 12:
Grand Rapids... 27 (1920)
Muskegon....... 27 (1940)
Lansing........ 29 (1995)
Kalamazoo...... 28 (1920)

Record low temperatures for November 13:
Grand Rapids... 10 (1986)
Muskegon....... 11 (1911)
Lansing..........1 (1872)
Kalamazoo...... 12 (1986)

&&

GRR watches/warnings/advisories...
Michigan...Winter Storm Warning until 5 PM EST Tuesday for miz064-071.

Lakeshore flood advisory until 5 PM EST Tuesday for miz064-071.

Winter Weather Advisory until 5 PM EST Tuesday for miz037-038-
043-050-056.

Lm...Small Craft Advisory until 11 PM EST Tuesday for lmz844>849.

&&

$$

Update...mjs
synopsis...Meade

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