Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 240002

Area Forecast Discussion
National Weather Service Northern Indiana
702 PM EST Thu Feb 23 2017

Issued at 701 PM EST Thu Feb 23 2017

It will remain unseasonable warm through Friday. Rain chances
will increase later tonight as low pressure develops in the
Plains. Severe weather remains a possibility Friday afternoon and
evening as a cold front moves through the area. High on Friday
will be in the middle 60s to the lower 70s in spots, then plummet
back to seasonable levels for the weekend along with a chance for
snow showers.


.SHORT TERM...(This Evening through Friday)
Issued at 248 PM EST Thu Feb 23 2017

Cold front in association with sw disturbance crossing srn ON this
aftn stalling now through cntrl IL/IN and will quickly reverse this
evening in response to upstream cyclone spinning up through wrn KS.
Fairly vigorous low level theta-e surge expected mid to late evening
in concert with nwd spread of ramping low level flow although better
implied forcing exists through wrn OH late evening.

Warm front mixes rapidly north into lower MI late tonight as sfc low
lifts into ern IA. Capping inherent to steep elevated mixed layer
likely to squash any warm sector convective development until mid
aftn at the earliest tied to prospects of arrival of better low
level moisture and upticking sfc based destabilization. Conditional
severe risk based on moisture availability appears greatest along
prefrontal trough feature through ern IN/wrn OH late aftn/early
evening where best overlap of 0-3km shear/MLCAPE ~1200 j/kg exists
suggesting a discrete supercell threat and all modes of severe wx
possible. Secondary concerns would lie along strongly forced cold
frontal zone farther west Fri evening through nrn IN/srn MI as more
unidirectional flow here indicates primarily a wind threat...
sweeping ewd through wrn OH late evening. Otherwise given as yet
still considerable spread present in highres solutions will follow
blended pops Fri aftn/eve.


.LONG TERM...(Friday Night through Thursday)
Issued at 248 PM EST Thu Feb 23 2017

Trailing H7-5 deformation zone will wrap ewd late Fri night/early
Sat morning along with brief lake enhancement as strong low level
cold advection wing follows in. Some minimal accums possible
northwest Sat am however rapid liftout of parent cyclone into se
Canada along with loss of mid level moisture plume along with
collapsing lake MI thermal trough Sat evening warrant an aggressive
cut to prior gridded pops.

Thereafter flow backs quickly Sun downstream of renewed broad
troughing through the wrn US which leads to rapid temp moderation
and returning rain chances by Tue.


.AVIATION...(For the 00Z TAFS through 00Z Friday Evening)
Issued at 701 PM EST Thu Feb 23 2017

latest radar trends show weak returns advecting into nw IN while
the sfc wmfnt was situ to the south across central IN. The best
opportunity for precip at KSBN will be 00-04Z while KFWA will be
after 05Z. After the initial round of precip i the early part of
tonight the next opportunity will be Friday afternoon as the sfc
coldfnt approaches. Will go with a vicinity mention of thunder at
KSBn starting 20z and for KFWA should be after the fcst period.
Winds will be gusty tmrw aftn from the south with gusts to 25
kts. Cigs should remain MVFR at KFWA while dropping to IFR at
KSBN around 13Z Fri.




SHORT TERM...Holsten
LONG TERM...Holsten

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