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Area forecast discussion 
National Weather Service Indianapolis in
1026 PM EDT Monday Aug 29 2016

the aviation section has been updated below.


issued at 330 PM EDT Mon Aug 29 2016

A warm and humid airmass remains in place across central Indiana,
but a break is on the way as a frontal system will move through
the area mid week, providing additional thunderstorm chances. This
front will be followed by cooler, drier air and a break from
recent daily rains.


Near term /overnight/...
issued at 954 PM EDT Mon Aug 29 2016

A nice reprieve from the active weather pattern as only small
isolated showers were able to generate under the upper ridge.
These were gone shortly after 00z with mainly clear skies ongoing.
0130z temps ranged from the mid 70s to lower 80s.

Quiet night in store as the ridge aloft centered across the Ohio
Valley will keep dry conditions and mainly clear skies. Remains
humid but short range guidance continuing to advect slightly drier
air present over Northern Ohio into the northeast forecast area
prior to daybreak. Regardless of that...the light flow and clear
skies combined with plentiful moisture in the near surface layer
all supportive of fog and have introduced into the grids for the
overnight. Bumped lows up a couple degrees at kind with a light
easterly flow expected...otherwise no changes needed.

Zone and grid updates out.


Short term /Tuesday through Thursday/...
issued at 330 PM EDT Mon Aug 29 2016

With surface high pressure nudging into the area tomorrow, expect
a bit of a break from storm chances over much of the area, but
will have to carry slight chance pops across the far west in the
afternoon as a weak upper level disturbance approaches.

More substantial thunder chances will be required Wednesday as a
cold front moves through the area. Dynamics are weak as is typical
so little severe threat is expected. Heavy rain and Hydro concerns
will again be the main issue. Beyond Wednesday high pressure will
overspread the area, allowing for a return to dry weather that
appears likely to persist into the weekend.

Consensus numbers appeared reasonable if slightly cool in spots on
Max temps, particularly tomorrow when models may be overdoing quantitative precipitation forecast
and resultant impact on temps. Minor adjustments made.


Long term /Thursday night through Monday/...
issued at 200 PM EDT Mon Aug 29 2016

Models in and ensembles in good agreement that benign weather is in
store for late week, and the weekend.

The late week will see an upper ridge over the central United States
and an upper trough over New England and the eastern Great Lakes.
Meanwhile, broad surface high pressure will be from Hudson Bay to
the Southern Plains. This will result in cool and dry weather
Thursday night with regional blend lows in the 50s looking good. The
upper ridge will point toward the Great Lakes late Friday as the
surface high moves into the eastern Great Lakes. Later in the
weekend, the high will be over New England, which will allow
temperatures and humidity levels to gradually rebound. Return flow
will increase even more early next week ahead of an approaching cold
front. This could result in a few storms northwest by Monday.

The regional blend temperatures start off below normal with highs in
the mid and upper 70s Friday and then increase to near normal by
Sunday with highs in the lower to mid 80s. So, no reason to deviate
with such good model agreement.


Aviation /discussion for the 300300z kind taf update/...
issued at 1026 PM EDT Mon Aug 29 2016

No significant changes made to the forecast at this time. Previous
discussion follows.

A few showers occurring over parts of the area, but for the most
part thunderstorm activity has failed to materialize as the air
mass is quite a bit less unstable than it has been recently.
Diurnal clouds based around 035 expected to fade out with sunset.

Otherwise, crossover temperatures are probably within reach
towards sunrise on Tuesday, although a light gradient advecting in
slightly lower dewpoints should keep any visibility restrictions
above IFR for the most part.

Surface winds 6 kts or less tonight.


Ind watches/warnings/advisories...none.



near term...Ryan
short term...nield

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