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000
FXUS63 KIND 221334
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
934 AM EDT THU SEP 22 2016

.UPDATE...
The NEAR TERM Section has been updated below.

&&

.SYNOPSIS...
Issued at 240 AM EDT Thu Sep 22 2016

High pressure will continue to provide dry and warm conditions into
the weekend. Next week, a frontal system will bring chances for rain
and cooler temperatures.

&&

.NEAR TERM /This afternoon/...

Issued at 924 AM EDT Thu Sep 22 2016

Surface analysis late this morning shows High pressure over NY and
PA...extending SW across the Ohio River Valley. Low pressure wad
found over Nebraska...along with a warm front that extended
northeast to Wisconsin and Michigan. Aloft water vapor Imagery
showed a large ridge of High pressure stretching from Texas into
the Ohio valley and through the deep south.

The High pressure system will continue to provide dry and
unseasonably warm weather today to central Indiana this afternoon.
Forecast soundings continue to show a dry column this afternoon
with unreachable convective temps. Thus will only look some high
Cirrus Clouds this afternoon. Given the full sunshine and little
change in air mass trended highs slightly warmer than yesterdays
highs.

&&
.SHORT TERM.../Tonight through Saturday night/
Issued at 240 AM EDT Thu Sep 22 2016

Focus is on any chances for rain later in the period as well as on
sky and temperatures. For the most part, models are close enough
that a blend was used, unless as noted below.

Upper ridging will remain in the area through the period. The center
of the ridge may move back west a bit, but believe central Indiana
will still remain under its influence.

A back door cold front will try and sneak into the area during the
weekend. With the ridging nearby, went closer to the models that
keep the front farther east. Even if the boundary does make it in,
the significantly cooler air will remain east of the area. In
addition, this front will not have any support with it, and
moisture/forcing with the front itself will be weak.

Thus feel dry conditions will persist through the short term. There
will be periods of partly cloudy skies for some locations with
clouds from convection to the north and east getting into the area,
and perhaps some from the front itself.

Continued with going above guidance for highs Friday, and went
closer to the warmer of the guidance numbers on Saturday since the
stronger push of the cooler air will be east of the area.

&&

.LONG TERM /Sunday through Wednesday/...
Issued at 320 AM EDT Thu Sep 22 2016

The strong upper ridge of high pressure over the weekend will break
down by the middle of next week as an upper trough moves east across
Canada and the northern U.S. and eventually digs into the great lakes.
There are timing differences between models on how fast this happens
and the arrival of the cold front next week.   The GFS has consistently
been to quick to break down the upper ridge...while the CMCNH model has been
a bit slow through Tuesday.  Prefer going with a CMCNH EURO blend which
breaks this upper ridge down a little slower and brings the cold front
our way late Tuesday/early Wednesday.

As a result will keep most areas dry prior to Monday and only go no more
than slight chance POPS monday.   Even downplayed rain chances a little
some areas Tuesday.  Went with chance pops Tuesday night on as cold front
moves through our area.

Unseasonably warm temperatures will be the rule early on in the long term and
cool to near normal by the middle of next week.   Tweaked high temperatures
a little warmer through Tuesday as the GFS has been too quick to cool us off.

&&

.AVIATION /Discussion for 221200z TAF Issuance/...
Issued at 700 AM EDT Thu Sep 22 2016

VFR most areas through the period.  However MVFR fog possible for the first
hour at KBMG and possible IFR fog KBMG late tonight.

High pressure will continue over the area.  A dying thunderstorm complex
moving into the great lakes may produce some mid/high debris clouds over
northern Indiana.  Only scattered high thin clouds expected elsewhere.

Only other issue will be possible repeat of IFR fog possibly late tonight at
KBMG.  Otherwise...VFR at other sites.

Winds will be southwest up to 5 knots late morning through this afternoon
and near calm most other times.


&&

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

$$

SYNOPSIS...50
NEAR TERM...PUMA
SHORT TERM...50
LONG TERM....JH
AVIATION...JH