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fxus63 kiwx 111940 

Area forecast discussion
National Weather Service northern Indiana
240 PM EST Mon Nov 11 2019

issued at 240 PM EST Mon Nov 11 2019

The first widespread accumulating snow event of the season will
continue to impact the area into this evening. Arctic air then
overspreads tonight into Tuesday with lows in the teens tonight
and highs only in the low to mid 20s tomorrow. Heavy lake effect
snow bands will also develop in favored areas downwind of Lake
Michigan during this time with localized heavy snow amounts
expected. Quiet weather conditions are then expected mid week
through this weekend, though temperatures will remain below


Short term...(this evening through tuesday)
issued at 240 PM EST Mon Nov 11 2019

Blast of Arctic air, potentially record breaking for Tue highs and
Wed lows, and accumulating snow remains the story into tonight
and Tuesday.

Widespread synoptic snow within intense deformation pivot will
gradually taper off from west to east this evening, ending in Lima
Ohio by 11 PM or midnight. Totals in the 3 to 5 inch range are
expected for most, though localized amounts near 6 inches likely
near Pivot Point in south-central Michigan. Roads will be icy/snow
covered into tonight.

Transition to a significant lake effect snow event then still in the
cards this evening into Tuesday as lake aggregate troughing develops
in response to strong NNW trajectories/caa. Lake-700 mb temp
differentials pushing the low-mid 30s for a time in this intense cold air advection
regime, and bulk of the ascent taking place within a
deepening/lowering dgz, favors dendritic growth and higher snow
ratios/rates within more intense banding. An increasingly
dry/subsident regime aloft and backing flow will eventually do a
number on inversion heights and snow intensity/coverage by Tuesday

Current expectations are for decent inland penetration of banding
tonight given strong northerly flow connected in with long axis of
Lake Michigan and Lake Superior. With that said, hard to say
if/where banding will hold in for a decent time for counties just
south and east of the Winter Storm Warning
(elkhart/Kosciusko/Marshall/Fulton in/starke). Reduced visibilities,
cold sfc temps, and additional accums will likely allow at least
advisory level impacts to persist beyond the current 05z expiration
in these counties. An upgrade to warning cannot be ruled out in
Marshall/Starke/Elkhart counties if the southern end of more
dominant band settles in for a time. Much higher confidence for
additional 6" plus snow amounts and intense 1-2" snowfall rates in
areas currently under a Winter Storm Warning. Latest guidance
continues to suggest Berrien, far western Cass Michigan and St Joseph in
in line for longest duration in intense lake plume where localized
totals will likely exceed a foot. Winds will also pick up on the
western fringe which could create some blowing/drifting.


Long term...(tuesday night through monday)
issued at 240 PM EST Mon Nov 11 2019

A clipper system will follow with the next chance for light snow
later Wednesday into Thursday morning. The bulk of model guidance
has this upper wave dampening as it reaches the Great Lakes region
with more pronounced isentropic bypassing north. Will hold with low
to mid chance pops and little snow accumulation as a result. The
rest of the forecast continues to look quiet, though temperatures
will remain well below seasonal norms.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1220 PM EST Mon Nov 11 2019

Kiwx radar indicating moderate/heavy snow band impacting ksbn attm
while lighter returns in vicinity of kfwa resulting in dz/fzdz
with both locations experiencing IFR/LIFR cigs/vsbys and expect
this to continue into this evening. Href members all in general
agreement with timing of synoptic snow to depart kfwa area shortly
after 00z while a quick transition from synoptic to lake effect
expected at ksbn. This will have kfwa improving to MVFR then VFR
while ksbn will still have IFR vsbys in the lake effect bands for
remainder of this taf cycle.


Iwx watches/warnings/advisories...
in...Winter Weather Advisory until midnight EST /11 PM CST/ tonight
for inz005>009-012>018-020-022>027-032>034.

Lakeshore Flood Warning until 4 PM CST Tuesday for inz003.

Winter Storm Warning until 5 PM EST /4 PM CST/ Tuesday for

Michigan...Winter Weather Advisory until midnight EST tonight for

Lakeshore Flood Warning until 5 PM EST Tuesday for miz077.

Winter Storm Warning until 5 PM EST Tuesday for miz077-078.

Ohio...Winter Weather Advisory until midnight EST tonight for ohz001-

Lm...Small Craft Advisory from 11 PM this evening to 11 PM EST
Tuesday for lmz043-046.

Gale Warning until 11 PM EST this evening for lmz043-046.



short term...steinwedel
long term...steinwedel

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