Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 162356

Area Forecast Discussion
National Weather Service Northern Indiana
756 PM EDT Sat Jun 16 2018

Issued at 740 PM EDT Sat Jun 15 2018

Hot and humid weather will persist through the remainder of the weekend
as an upper level ridge remains over the region. An isolated
storm remains possible into this evening along and south of Route
30 across mainly northwest Indiana. Otherwise no rain is expected
through Monday morning. Lows tonight will only drop into the
lower 70s, with highs back into the mid 90s for Sunday, along with
afternoon heat indices around 100.


.SHORT TERM...(This Evening through Sunday)
Issued at 400 PM EDT Sat Jun 16 2018

Outflow boundary has slowed considerably, oriented from south of
Valparaiso to near Fort Wayne. While plenty of instability
exists, the few showers that have tried to form have struggled
against a strengthening inversion.Cu field slowly losing the fight
as well with vis sat showing less in the way of towering cu. Not
completely out of the woods for storms as we head towards evening
and the inversion weakens slightly with normal diurnal trends.
HRRR remains consistent in rapid development of storms along this
boundary. Will maintain slgt chc to chc pops in the SW areas into
early evening.

After this the heat will dominate as ridge continues to build into
the region with the hottest day so far (and maybe in a while) in
store for the area. Overnight lows will drop into the upper 60s to
lower 70s. This will give a great platform for temps to skyrocket
under what should be mostly sunny skies with highs reaching into
the middle 90s. Concerns have lingered about dewpoints, but with
upstream dewpoints across Illinois into central IN into the middle
70s see no reason it won`t come in to the area. After much
discussion with surrounding offices have hoisted heat advisory for
the entire area. Headlines may be needed into the long term
period, but didn`t want to lock next shift into anything further
at this point.


.LONG TERM...(Sunday Night through Saturday)
Issued at 400 PM EDT Sat Jun 16 2018

Heat and humidity will continue into at least Monday with
overnight lows Sunday night in the mid 70s and highs Monday in the
lower to middle 90s. Areas south of US-30 could see heat indices
approach criteria once again but as noted in short term will not
issue anything beyond Sunday. Heat and humidity will become less
of a concern for the work week.

Frontal boundary will sink south into the area Tuesday as ridge
begins to lose its influence and flatten some. Weak disturbances
will ride along the edge of the ridge the remainder of the
forecast period to bring chances of precip. The best chances at
this point looks to be Tues into Tuesday night as well as towards
the end of the period when most pronounced waves move in.


.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 740 PM EDT Sat Jun 16 2018

The threat of showers and thunderstorms has diminished across the
terminals early this evening. Earlier outflow boundary which
dropped south of the terminals has shown some signs of slight
northward retreat. An isolated shower has developed along this
boundary over the past hour to the southwest of KPPO in northwest
Indiana. This boundary may trend to continue to lift northeast
over the next few hours, although some surface based CIN will be
developing after sunset which will limit additional shower
potential. Bulk of shower and thunderstorm coverage has been
confined to OH/east central IN, in association with weak MCV that
emanated from earlier convection. With this forcing mechanism not
likely to affect terminals, will go with a dry terminal forecast
this evening. Moderate sfc based instability expected to develop
on Sunday, although magnitude of instability will be more
tempered due to slightly weaker mid level lapse rates. Gradient
should provide southwest winds in the 10 to 15 knot range with
diurnal mixing by mid morning Sunday. VFR conditions are expected
to persist throughout this forecast cycle.


IN...Heat Advisory from 11 AM EDT /10 AM CDT/ to 8 PM EDT /7 PM CDT/
     Sunday for INZ003>009-012>018-020-022>027-032>034.

MI...Heat Advisory from 11 AM to 8 PM EDT Sunday for MIZ077>081.

OH...Heat Advisory from 11 AM to 8 PM EDT Sunday for OHZ001-002-004-



LONG TERM...Fisher

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