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Area forecast discussion 
National Weather Service Indianapolis in
1019 am EDT Thu Oct 27 2016

aviation section updated


issued at 348 am EDT Thu Oct 27 2016

Low pressure over northern Indiana and a trailing cold front across
west central Indiana will move east across our region by midday
High pressure over the upper Midwest will move east across Indiana

A mild southerly flow will develop on the back side of this high
pressure system Friday as it moves on to the east. Unseasonably
mild conditions will occur Saturday and again early next week as a
strong upper ridge builds over the southern U.S. A weak frontal
system will move our way and stall over northern sections Sunday and
then move back to the north. Another weak frontal system will move
our way around the middle of next week.


Near term /rest of today and tonight/...

Issued at 945 am EDT Thu Oct 27 2016

rain has ended across central Indiana as a low pressure system and
associated cold front push farther east. Current forecast is on
track, so no changes. Current temps across the area are generally
in the upper 40s/low 50s and are expected to top off in the mid
50s to low 60s. Updated grids have been sent.

Previous discussion...
low pressure was over northern Indiana and a weak cold front
extended southwest across west central Indiana and southern
Illinois. The cold front will move rapidly east across central
Indiana this morning as the low pressure system moves towards the
eastern Great Lakes.

Radar indicated widely scattered light showers were occurring over
central Indiana and a few areas in eastern Illinois were reporting
patchy drizzle. Could a few light showers or patchy drizzle over
the eastern half of our region early this morning. Satellite and
weather depiction indicated lots of low clouds upstream to our
west and cloudy skies should persist well into the afternoon
before breaking up late today.

Will go with partly cloudy conditions late today and early tonight
with some areas becoming mostly clear later tonight. Temperatures
will fall into the lower 50s or lower after the cold front moves
through and remain in the 50s most areas later today. Went with
highs from the lower 50s northwest to around 60 far southeast.

With light winds and clearing tonight went a little cooler with lows


Short term /Friday through Saturday night/...
issued at 348 am EDT Thu Oct 27 2016

The high pressure system which will move across Indiana tonight will
move on to the east Friday and a milder southerly flow on the back
side of this high will allow temperatures to become warmer Friday.
With lots of sun and warm advection went a little warmer than MOS
temperatures. Highs Friday will be from the middle 60s northeast
to the lower 70s southwest.

The rest of the short term period will be unseasonably mild with a
moderate southerly flow. Models indicate a strong upper ridge will
build over the deep south. Lows will be in the middle 50s Friday
night and middle to upper 50s Saturday night. Highs Saturday will
be in the middle to upper 70s.

Believe super blend winds are too light Saturday and went closer to
cancer values. Could see winds gusts 20 knots or higher Saturday.

A weak cold front will stall across the northern parts of our region
by Sunday. This front could bring a few showers to northern areas
late Saturday night.


Long term /Sunday through Wednesday/...
issued at 348 am EDT Thu Oct 27 2016

Ensembles are in fairly good agreement during this period. A short
wave trough is expected to be passing east through the Great Lakes
on Sunday. Will keep a lingering chance pop over mainly the
northeastern zones during the day Sunday to cover the exiting system.

Otherwise, the ensembles indicate upper ridging will build over the
southeast parts of the country, as a trough lifts northeast through
the plains into the western Great Lakes during the early to middle
parts of next week. As a result, will bring in chance pops for
Tuesday night into next Wednesday.

Temperatures expected to be well above normal given the upper


Aviation /discussion for the 271500z ind taf update/...

Satellite shows abundant stratocu across Illinois...Indiana and
Wisconsin...upstream of the current taf sites. Forecast soundings
and time height sections show trapped lower level moisture
lingering across the area through the afternoon. Thus the ongoing
MVFR ceilings are expected to continue for the next 6-9 hours.

Ongoing tafs handle this okay.

Previous discussion below

/discussion for the 271200z tafs/...
issued at 631 am EDT Thu Oct 27 2016

Some areas of ceilings 006-009 above ground level still being observed across the
area. These ceilings may linger until 271300z-271400z, but overall
the lower ceilings should continue to lift with time as drier air
works in at the lower levels.

Otherwise, MVFR ceilings extend well upstream in the Post frontal
zone, so think these ceilings will hang around most of the day,
aided by a developing subsidence inversion based around 025-030.

Surface winds 280-310 degrees at 9-13 kts this morning, gradually
veering to 310-340 degrees at 5-8 kts by late afternoon. Occasional
surface gusts 18-20 kts early this morning expected to end over
the next few hours as pressure gradient relaxes in the wake of
frontal passage.


Ind watches/warnings/advisories...


near term...tdud/jh
short term...jh
long term...jas

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