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Area forecast discussion 
National Weather Service Indianapolis in
920 PM EST Tuesday Nov 24 2015


The near term section has been updated below.


issued at 312 PM EST Tuesday Nov 24 2015

High pressure will result in dry conditions and a weak warming
trend through mid-week. However...a broad upper level low and an
associated surface low and cold front will bring rain chances
starting Wednesday night through Friday. This frontal system will
stall out south of Indiana over the weekend and then a more potent
system will enter the Central Plains late in the extended
period...resulting in a prolonged period of rain.


Near term /tonight/...
issued at 920 PM EST Tuesday Nov 24 2015

Forecast looks in good shape at this time. No updates planned.
Previous discussion follows.

A large area of high pressure at the surface will encompass the
eastern third of the U.S. Tonight. Meanwhile...ridging aloft will
keep central Indiana dry. So...the main focus will be temperatures and
sky cover for the near term period. A dry warm front will pass
from southwest to northeast across the forecast area tonight
resulting in increased cloud cover and warmer overnight lows.
Models are leaning toward overnight lows in the low 30s across the
northern counties to upper 30s over the southern counties.


Short term /tomorrow through Friday/...
issued at 312 PM EST Tuesday Nov 24 2015

The main focus of the short term period will be rain chances on
Thursday and Friday as a low pressure system and associated cold
front traverse the area.

Central Indiana will remain dry through Thursday with ridging in
place aloft. However...the ridge will break down by Wednesday
night as a broad upper low strengthens over the western u...
rain chances will begin across northwestern central Indiana as low
pressure and cold front push through the region. Highest rain
chances across the forecast area will be on Thursday night and
Friday as dynamics intensify with cold front passage.

Temperatures through the period will gradually warm with
south/southwesterly flow. So...trended toward the warmer side of
mavmos through the short term period.


Long term /Friday night through Tuesday/...
issued at 207 PM EST Tuesday Nov 24 2015

Focus this weekend and early next week will be on rainfall.

Models and ensembles in general consensus with the synoptic pattern
this weekend and early next week. Blend has an upper low over the
Great Basin at the start of the period moving to the Great Lakes by
next Tuesday. At the surface...models have a front stalling south of
the Ohio River early in the long term. Models also agree that this
stalled low pressure system will retool as energy from the upper low
moves over the area in southwest flow. This southern system and
possibly another will lift northeast over the area late this weekend
and early next week. With Gulf moisture streaming back to the
north...the potential is there for prolonged rain.

Would not rule out a mix with snow during the nighttime
hours...especially Monday night and across the northern counties.

With southerly flow but widespread cloud cover...expect near normal
temperatures with highs mostly in the 40s and lows mostly in the 30s
per regional blend.


Aviation /discussion for the 25/00z tafs/...
issued at 615 PM EST Tuesday Nov 24 2015

VFR through the period.

Likely to see only high cloud through the period as surface high
pressure lifts out of the area.

Winds will be less than 10kt overnight...becoming southerly at 10-
14kt with gusts to around 20kt during the day on Wednesday.

No obstructions to visibility anticipated during the period.


Ind watches/warnings/advisories...none.



near term...tdud/jas
short term...tdud

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