Area Forecast Discussion
Issued by NWS Northern Indiana

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FXUS63 KIWX 231800

Area Forecast Discussion
National Weather Service Northern Indiana
200 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...(This Evening through Sunday)
Issued at 156 PM EDT Sat Jul 23 2016

Convective complex currently moving through the upper MS valley as
short wave energy from the plains impinges on upper ridge this
afternoon. Latest Meso-analysis indicating sharp instability and
Theta-E gradient and expect complex to continue eastward into the
great lakes region along this boundary. HIRES guidance suggesting
southern edge of this complex may clip our far N/NW CWA later
tonight so will follow current forecast of chance/slight chance POPs
in this area.

Cold front approaching the region on Sunday will provide synoptic
scale forcing to act on unstable warm sector airmass to bring
another chance for thunderstorms to the area. Debris clouds from
previous nights convection may initially hinder destabilization but
still expect CAPE in excess of 3000J/kg by late afternoon. Despite
good instability expect a weakly sheared environment to limit any
severe potential. Areal coverage still somewhat in question so will
keep POPs in chance range. With additional cloud cover expected
Sunday will hold off on any further heat advisories for now and see
how nocturnal convection evolves...have adjusted maxT down a degree
or two to account for this.


.LONG TERM...(Sunday Night through Saturday)
Issued at 156 PM EDT Sat Jul 23 2016

Frontal passage may linger into Monday for the southern CWA as front
becomes more E-W oriented. Models also have varying solutions for
timing of front to clear our area so will continue with small chance
in the south. High pressure then builds into the region on Tuesday
and will bring temps back into the 80s and closer to normal along
with less humid conditions which will allow for more comfortable
overnight lows in the mid 60s. Upper flow becomes more zonal and
will keep temps near normal for the remainder of the forecast
period. Pacific energy streaming in on zonal flow will bring precip
chances back into the forecast by the end of the week.


.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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