000
FXUS63 KIND 272308
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
708 PM EDT TUE SEP 27 2016

.UPDATE...

The Aviation section has been updated below.

&&

.SYNOPSIS...
Issued at 221 PM EDT Tue Sep 27 2016

An upper level low is expected to drift southeast from the
upper Great Lakes into the Appalachian mountain region towards
the end of the week.

&&

.NEAR TERM /Tonight/...

Issued at 659 PM EDT Tue Sep 27 2016

Slowed temperature fall first few hours as healthy breezes keep
mixing up. Winds should stop gusting before sundown and lay down
some at that time as well...allowing bit more rapid cooling.

Cloud deck should reach northern counties by mid evening and
overspread all of central Indiana by or shortly after midnight.

Still expecting chance for showers towards daybreak.



&&

.SHORT TERM /Wednesday through Friday/...
Issued at 221 PM EDT Tue Sep 27 2016

Models suggest strong vorticity lobe, in conjunction with upper
low, will move through the local area during the day on
Wednesday. Will continue with chance PoPs all areas on Wednesday.
Steepening mid level lapse rates during the day suggest some
lightning strikes are possible, especially over the southeast
zones, where passage of vorticity lobe will coincide with peak
heating.

Appears some shower threat will probably linger through Friday
as upper low gradually drifts southeast into the Appalachian
mountain region towards the end of the period. Will keep chance
PoPs in the forecast through Friday all areas for now, but it
appears the best threat will be over the eastern and southeastern
zones after Wednesday, closest to upper low.

Based on progged low level thicknesses, the GFS MOS highs for
Wednesday and Thursday look too cool. Will raise the guidance a
category or so in those periods. Guidance lows look OK for now.

&&

.LONG TERM /Friday Night through Tuesday/...

Issued at 220 PM EDT Tue Sep 27 2016

The ECMWF continues to keep the persistent upper low over the
Ohio Valley Friday night through Saturday...before it finally
begins to drift farther north on late Saturday night and Sunday.
ECMWF then suggests ridging aloft build across the
region...nudging the low to the northeast. Thus have kept with
superblends low chance pops from Friday Night into Saturday...then
trended toward a dry forecast early next work week as ridging and
high pressure resume. Expect below normal temperatures to continue
on Friday and early Saturday as the low lingers in the area...a
return to near normal highs is expected next work week as high
pressure builds across the region and warmer southerly flow tries
to develop.

&&

.AVIATION /Discussion for the 28/00z TAFs/...
Issued at 708 PM EDT Tue Sep 27 2016

VFR conditions may give way to MVFR in stratus and showers late
tonight into Wednesday morning across the sites as a large upper low
drops into the region.

Clear skies initially will quickly cloud up late tonight as the
upper low approaches. Fluctuations in conditions will be likely on
Wednesday, with the lowest conditions likely in any showers or
perhaps an isolated storm or two.

Winds will become more northwesterly with time, and will be 10kt or
less throughout the period.

Visibilities will be unrestricted except for minor restrictions in
precipitation.

&&

.IND Watches/Warnings/Advisories...NONE.

&&

$$

SYNOPSIS...JAS
NEAR TERM...TUCEK
SHORT TERM...JAS
LONG TERM...PUMA
AVIATION...NIELD