Area Forecast Discussion
Issued by NWS Indianapolis, IN

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FXUS63 KIND 261421

Area Forecast Discussion
National Weather Service Indianapolis IN
1021 AM EDT MON SEP 26 2016

Aviation sections updated


Issued at 306 AM EDT Mon Sep 26 2016

Colder and drier air will flow in behind a cold front today, ending
rain this morning. An upper low will bring more rain chances mid to
late week. Seasonable temperatures can be expected into next week.


.NEAR TERM.../Rest of Today/
Issued at 1003 AM EDT Mon Sep 26 2016

Radar indicates back edge of main band of rain band approaching the
southeast corner of the forecast area, although some lighter rain extends
a bit farther back to the west. Appears the rain threat will be over
across the area by early afternoon.

Cloud cover should gradually thin out from west to east later this
afternoon. Previous discussion follows.

Scattered to numerous thunderstorms were along and just ahead of a
cold front moving through central Indiana early this morning. More
showers, and isolated thunderstorms, were back across Illinois
closer to the 850mb temperatures/moisture gradient.

These features will continue to march east through the remainder of
the early morning. Will include a pre-first period in the text
product to account for these features.

By 12Z, feel that all the instability will be east of central
Indiana, so do not plan on including any thunder mention in the
Today period. At 12Z rain ahead of the 850mb boundary will continue
to be moving across much of the area so will go likely to
categorical PoPs for most areas. Far northwest will just be chance.

However, the forcing will quickly shift east during the morning, so
that by afternoon all areas are dry. The much drier air moving in
should also allow skies to become mostly sunny for the afternoon.

Cold advection will allow some wind gusts near 20kt in some areas
this afternoon.

For temperatures, feel that the sunshine will be strong enough to
overcome the cold advection and allow highs to be a little above the
MAV MOS guidance.


.SHORT TERM.../Tonight through Wednesday night/
Issued at 306 AM EDT Mon Sep 26 2016

Focus is on any chances for rain through the period. Models are
coming into better agreement with the upper low so used a blend.

High pressure will sneak into the area tonight and Tuesday, allowing
for mostly clear skies. Enough wind will mix down on Tuesday for
some gusts near 25kt at some locations. Winds should remain up
enough tonight to keep temperatures bottoming out, so went in
between the colder MOS and the warmer raw model blend. Went with a
model blend for highs Tuesday.

As an upper low sinks south through the vicinity Tuesday night into
Wednesday night, enough forcing will arrive for some slight chance
to low chance category PoPs for at least parts of the forecast
area during that period.

Clouds and scattered showers should keep temperatures down
Wednesday. Generally stayed with a model blend.


.LONG TERM /Thursday through Saturday Night/...

Issued at 345 AM EDT Mon Sep 26 2016

Latest model runs are differing substantially from previous runs
in regard to an upper low during the extended period. Earlier runs
were predicting a dry forecast for the majority of the long term
period, but now models have that upper low meandering over
portions of the Ohio Valley and Great Lakes Region. There is quite
a bit of difference between GFS and Euro in regard to track though
with the Euro taking more of an eastward propagation. As a
result, will not go any higher than the initialization`s slight
chance pops at any time from Thursday through Saturday. As far as
temps, the cooler pattern is still expected with highs generally
in the 70s and lows in the 50s.


.AVIATION /Discussion for the 261500z IND TAF update/...

VFR Conditions are expected to continue the next several hours.
Cold front and the majority of the associated precip with it has
drifted east of the TAF sites. Dry air and subsidence continue to
build across the region. Forecast soundings suggest unreachable
convective temps...thus will just play with the clouds as seen
upstream...mainly VFR CIGS passing through over next 3-5 hours.

Previous discussion below

/Discussion for the 26/1200Z TAF Issuance/...

Issued at 714 AM EDT Mon Sep 26 2016

Scattered showers will linger through mid morning across central
Indiana, but they will have limited impact on flight operations
with KHUF being the only TAF site with MVFR conditions at this
time. As cold front pushes farther east today, drier air will
filter into the area, and all TAF sites will become VFR at that
point. VFR will then prevail through the end of TAF period. Winds
will generally be west/southwesterly at 5 to 11 kts.


.IND Watches/Warnings/Advisories...


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