Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 231737

Area Forecast Discussion
National Weather Service Northern Indiana
137 PM EDT SAT JUL 23 2016

Issued at 414 AM EDT Sat Jul 23 2016

A hot and humid airmass will remain over the area this weekend.
Isolated thunderstorms are possible south of U.S. route 30 this
afternoon along a weak stationary front. A cold front will move east
from the central and northern plains tonight, possibly causing
thunderstorms to move into northwest portions of our area by
daybreak Sunday. This front is expected to move across the area
Sunday night and Monday with storms again possible along and ahead
of the front. Hot and humid conditions are expected to continue
until the front moves through, with a little cooler and drier
conditions expected by Tuesday and Wednesday. Highs today and Sunday
are expected to be in the lower 90s with lows tonight in the lower


.SHORT TERM...(Today through Sunday)
Issued at 414 AM EDT Sat Jul 23 2016

Upr level ridge over the plains will build east today ahead of
shrtwv pushing into the nrn plains. Warmer temps aloft and
subsidence associated with the apchg ridge should enhance capping
inversion and limit or prevent deep convection in our area today.
Hwvr, left a slight chc of tstms in across swrn portion of cwa
for potential of storms developing along stalled sfc boundary
with psbl boost in convergence from srn Lake MI lake breeze.
Sufficient sunshine expected to allow temps to climb into the
l90s, except a little lower near Lake Michigan due to lake breeze.
Dwpts currently in the l70s across much of the area (a little
lower across srn mi) should be maintained with wk flow, or perhaps
rise a bit due to evapotranspiration. This should allow heat index
readings to meet or exceed advisory criteria (around 100) across
nrn IN/nwrn OH, prbly just blo that across srn MI.

Nrn plains shrtwv/cdfnt expected to move east to the upr ms
valley tonight. Tstms expected to move out ahead of the front,
psbly reaching nwrn portion of our cwa by daybreak Sunday. Fair
agreement among hires models that this activity will weaken Sunday
morning, then reform as cdfnt approaches nwrn portion of the cwa
in the aftn, hwvr, GFS seems to indicate storms could persist
longer and impact our area in the morning, so for now have opted
to leave chc pops in all day. Given the uncertainty with
convection evolution/debris cloudiness, felt best attm not to
extend heat advisory into Sunday, but that may need to be done
today or tonight, once more confidence in convective trends is


.LONG TERM...(Sunday night through Friday)
Issued at 414 AM EDT Sat Jul 23 2016

Cdfnt expected to move through the cwa Sunday night/Monday.
Continued a chc of tstms until front moves east of the area. A
little cooler (near normal) and drier post-frontal air expected
Tue/Wed as high pressure moves east from the central/nrn plains
across the grtlks. More zonal flow across the nrn U.S. with a
broad trof over the upr grtlks expected late in the week may
result in periodic shrtwv`s impacting our area. Models
timing/track of these quick moving systems is in poor agreement
attm, so just low pops warranted attm. Temps should remain near
normal through this timeframe.


.AVIATION...(For the 18Z TAFS through 18Z Sunday Afternoon)
Issued at 133 PM EDT Sat Jul 23 2016

Expect VFR conditions through the period. Kept a dry fcst this
aftn with a mention of VCTS tonight between 06 and 12Z. Otherwise
light WSW winds this aftn then variable tonight.


.IWX Watches/Warnings/Advisories...
IN...Heat Advisory until 8 PM EDT /7 PM CDT/ this evening for

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




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