Area Forecast Discussion
Issued by NWS Northern Indiana

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000
FXUS63 KIWX 220139
AFDIWX

Area Forecast Discussion
National Weather Service Northern Indiana
838 PM EST Wed Feb 21 2018

.SYNOPSIS...
Issued at 302 PM EST Wed Feb 21 2018

Widespread significant flooding will continue over northwest
Indiana and southwest lower Michigan. Moderate to major flooding
is expected along main rivers and some record crests are possible.
It will be much cooler tonight with a wintry mix tonight over
areas east and south of Fort Wayne.

&&

.UPDATE...
Issued at 838 PM EST Wed Feb 21 2018

Aftn based near term highres guidance running a bit hot compared to
latest 00Z run which have tempered back and rightly so considering
00Z raobs which are quite dry through wrn arc of mid level
subsidence zone. H7 based moisture advection/ascent does become
quite robust toward sunrise within the US24 corridor and suggestive
of an wintry mix zone extending nwwd into the Peru-Fort Wayne areas,
which timed with threshold min temps around freezing, may yield some
travel problems yet. However per waffling highres trend will hold
off on potential advisory expansion in consideration of additional
00Z based guidance.

&&

.SHORT TERM...(This Evening through Saturday)
Issued at 302 PM EST Wed Feb 21 2018

A major flood event is underway over northwest Indiana and far
southwest Lower Michigan. Have continued areal flood warnings for
these areas. Will allow the flood watch for the remainder of the
area to expire; however, have issued a Hydrologic Outlook for more
rain over areas from Fort Wayne south.

Have also issued a winter weather advisory for this same area. A
shallow wedge of cold air is expected to bring a wintry mix
including freezing rain and sleet. The surface temperatures
tonight will be very critical as readings drop slightly below
freezing.

&&

.LONG TERM...(Saturday Night through Wednesday)
Issued at 302 PM EST Wed Feb 21 2018

A tranquil period is ahead next week as the upper level trof stays
well to the west of the area. Temperatures should be well above
normal in the 40s and 50s with limited rainfall.

&&

.AVIATION...(For the 00Z TAFS through 00Z Thursday Evening)
Issued at 605 PM EST Wed Feb 21 2018

Post frontal inversion holding tough and little change noted in
extensive/widespread MVFR stratus wedge across the terminals. Latest
numerical guidance keeps this in place overnight and not surprising
given concurrent extensive mid to high cloud plume in place.

Otherwise some growing concern with significant moisture plume
taking shape across the lower MS valley. Broad near term highres
guidance trending sharply left (northwest) with precipitation shield
after midnight which overlapped with progged sfc temps suggest icing
threat may spread much further nw then previously anticipated. Plan
for the time being is to await 00Z sounding data along with upstream
radar/sat trends before reaccessing but changes likely forthcoming
later this evening along with potential amendments invof KFWA.

&&

.IWX WATCHES/WARNINGS/ADVISORIES...
IN...Winter Weather Advisory from 1 AM to 11 AM EST Thursday for
     INZ026-027-032>034.

MI...NONE.

OH...Winter Weather Advisory from 1 AM to 11 AM EST Thursday for
     OHZ016-024-025.

LM...Small Craft Advisory until 10 PM EST this evening for LMZ043-
     046.

&&

$$

SYNOPSIS...Lashley/Skipper
UPDATE...T
SHORT TERM...Skipper
LONG TERM...Skipper
AVIATION...T


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