Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 182301

Area Forecast Discussion
National Weather Service Northern Indiana
701 PM EDT Mon Jun 18 2018

Issued at 236 PM EDT Mon Jun 18 2018

A heat advisory remains in effect through this evening highs
rising to between 90 and 95 and heat indices to around 100.
Isolated showers and storms are possible through this evening
near Michigan border. Somewhat cooler air will spread into the
area for the rest of the week and be accompanied by periodic
chances for showers and thunderstorms storms. Some storms may
produce very heavy rainfall on Tuesday.


.SHORT TERM...(This Evening through Tuesday)
Issued at 236 PM EDT Mon Jun 18 2018

The fcst area remains under a heat advisory through this evening
as temperatures have climbed through the 80s early this aftn.
Expect temperatures to top out in the low to mid 90s with heat
indices over 100 most places. Convection that was occurring to the
north across MI this morning has dissipated with some
redevelopment along and north of I90. HiRes models point to
scattered convection across the northern half of the area then
dissipating after 03-04Z. There should be a lull overnight and
then another round of thunderstorms Tue aftn. CAPE values are well
above 2000 this aftn and is expected for Tue. Precip water values
have been 1.5 to 1.75 today are fcst to rise to around 2 inches
by Tue. The frontal boundary oriented e-w just to our north today
will sink southward overnight and be situ across U.S. 30 by Tue
aftn where the precip focus should be for tmrw into tmrw night. A
marginal risk for svr exists into tonight with isolated damaging
wind being the primary threat. With the boundary shifting
southward the threat area focuses on the southern third of the
fcst area Tue for both rainfall and isolated damaging wind.

Since the HiRes models do not keep thunderstorms ongoing through
the not think flooding will be an issue in the near
term even if individual storms are efficient rainfall producers.
However will mention in the weather story the potential for heavy
rains Tue aftn.


.LONG TERM...(Tuesday Night through Monday)
Issued at 236 PM EDT Mon Jun 18 2018

An upper low over the northern Rockies will translate into the
central plains during the midweek period reaching Illinois by
Friday. The low will meander as upper level ridging blocks
eastward movement of the low. As the ridge flattens the low lifts
newd into the Gtlks by the weekend. Ahead of this...our weather
pattern will remain unsettled with chances for precipitation most
days except Wed night/Thu. Temperatures are expected to be more
seasonal with highs in the upper 70s to lower 80s through the


.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 700 PM EDT Mon Jun 18 2018

KIWX radar showing widely scattered showers over the area this
evening with just a few lightning strikes. More organized line of
convection to the north over lake Michigan has been trending
weaker in the past hour but renewed convection along the northern
Illinois border. CAM models have been hot and cold with how this
convection will evolve tonight. Despite loss of daytime heating,
sufficient forcing along approaching frontal boundary will warrant
a prevailing group for SBN early tonight. Will then bring precip
chances back at both sites Tuesday afternoon as airmass
destabilizes and front stalls out over the area. Gusty southwest
winds should diminish tonight as gradient weakens with arrival of
front. Front expected to push through SBN after midnight and stall
near FWA. Low level moisture pooling in the vicinity of front
will have lowering ceilings with latest model guidance going down
to IFR. Will follow previous issuance and only go down to MVFR for
now and re-evaluate at 06Z cycle.


IN...Heat Advisory until 8 PM EDT /7 PM CDT/ this evening for

MI...Heat Advisory until 8 PM EDT this evening for MIZ077>081.

OH...Heat Advisory until 8 PM EDT this evening for OHZ001-002-004-005-




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