Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 081035
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
535 AM EST Thu Dec 8 2016

.SYNOPSIS...
Issued at 1223 AM EST Thu Dec 8 2016

A strong low pressure system moving slowly east across
southeast Canada will cause cold west to northwest winds across
the Great Lakes resulting in significant lake effect snow over
southwest Michigan and far northern Indiana over the next couple
of days, with scattered snow showers over northwest Ohio and most
of the rest of northern Indiana. A low pressure system is
expected to move east across the Midwest this weekend causing snow
in our area, mainly Saturday night and Sunday. An arctic airmass
is expected to plunge southeast into the Great lakes region by the
middle of next week resulting in bitterly cold temperatures and
probably additional lake effect snows.

&&

.SHORT TERM...(Today and Tonight)
Issued at 534 AM EST Thu Dec 8 2016

Lake effect snow was already beginning north of Berrien county as
colder air was spreading over the relatively warms waters of Lake
Michigan. Few changes were made to the ongoing grids and forecast,
although have added Laporte County to the advisory given wintry
weather of blowing and drifting expected over far northern areas of
the county late today and tonight. The Lake Michigan water
temperatures over these southern portion of the lake around 45
degrees were exceptionally very warm for this time of year. Delta T
values will reach or exceed 20C with the cloud area very favorable
for snow growth. However, limited lake fetch, especially early along
with significant shear in the cloud layer will limit accumulations.
Have kept 5 to 8 inches over the advisory area, with lesser amounts
farther inland. Snow will diminish Friday as inversion heights
fall.

&&

.LONG TERM...(Friday through Wednesday)
Issued at 534 AM EST Thu Dec 8 2016

More cold and snowy weather is on the horizon for the extended.
Favor a general model blend for the approaching upper level system
this weekend. There was still considerable spread among GFS ensemble
members, so confidence in timing, track and snow amounts still
uncertain. Some members and the EC were warmer Sunday suggesting a
possible rain/snow mix. For now, kept all snow. Accumulations of
several inches are possible from Saturday through early Monday.
Otherwise, much colder air should spread over the area by Wednesday
along with snow and lake effect snow showers.

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1223 AM EST Thu Dec 8 2016

Deep low over james bay will move slowly east with a trailing trof
dropping sewd across the grtlks this taf period. Extensive strato cu
deck over the upr midwest/grtlks has been slowly advecting sewd into
nrn IN and this should continue overnight. Flurries upstream across
the upr midwest suggest decent low level moisture advecting toward
our area as well. This in combination with continued caa/increasing
inversion heights should lead to lake effect shsn developing early
this morning and then continuing and grdly intensifying through the
period with ifr conditions expected by this eve at sbn. Lower
inversion heights at fwa suggest just ocnl -shsn at this terminal
with mvfr predominating.


&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Winter Weather Advisory from 10 AM EST /9 AM CST/ this morning
     to 4 PM EST /3 PM CST/ Friday for INZ003>007.

MI...Winter Weather Advisory from 10 AM this morning to 4 PM EST
     Friday for MIZ080.

     Winter Storm Warning until 4 PM EST Friday for MIZ077>079.

OH...NONE.
LM...Small Craft Advisory until 7 PM EST Friday for LMZ043-046.

&&

$$

SYNOPSIS...JT
SHORT TERM...Skipper
LONG TERM...Skipper
AVIATION...JT


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