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Area forecast discussion 
National Weather Service Indianapolis in
656 am EDT Tuesday Sep 16 2014

the aviation section has been updated below.


issued at 350 am EDT Tuesday Sep 16 2014

A cold front over Kentucky will move on to the south as high
pressure centered over Iowa builds east into the southern Great
Lakes. This high pressure system will dominate our weather most of
this week as it moves east over the southern Great Lakes and
eventually New England late this week.

An upper ridge over the western U.S. Will build towards the Ohio
Valley Friday and Saturday which will allow temperatures to become
warmer as heights rise across our region. Models move a cold front
southeast across our region around Sunday. Temperatures will become
cooler after next weekend as an upper trough digs into the Great


Near term /today/...

Issued at 350 am EDT Tuesday Sep 16 2014

Satellite shows an extensive area of stratus across all but far
Northwest Indiana and central and southern portions of Illinois.
Clearing to our northwest will slowly spread into our region...but
given wet ground and light winds there may be some patchy fog
developing some areas near sunrise for a few hours. The sref model
indicates this would be most likely to occur across the northwest
half of our forecast area and it should burn off quickly after

Other than patchy early morning fog...the main forecast issue will
be how quick low clouds will clear out today. Model soundings
indicate southeast 2/3 of our region will start out mostly cloudy
and clouds will gradually break up during the day. Will slow down
clearing a little from previous forecast. Will go with mostly sunny
northwest half and partly cloudy southeast half this afternoon. With
more clouds in the south will lower high temperatures there a little
later today.


Short term /tonight through Thursday night/...
issued at 350 am EDT Tuesday Sep 16 2014

High pressure will move east across the southern Great Lakes early
on in the short term. Even later on it will still dominate our
weather as a ridge extends west from the high center across our
region. Models indicate a weak upper disturbance will move across
the lower Ohio Valley around Wednesday which may result with a
little more clouds over central and southern sections then.
Otherwise...mostly clear and dry conditions will be the rule through
the rest of the short term period.

Went close to a MOS blend on temperatures through the short term.
Models indicate 850 mb temperatures will be near +7 to +9 celsius
over northern sections and +10 to +12 celsius in the south.
There will be good radiational cooling at went a few
degrees lower some areas with overnight low temperatures..


Long term /Friday through Monday/...
issued at 350 am EDT Tuesday Sep 16 2014

High pressure will be over Indiana through Saturday keeping dry
weather over the state. Flow will become southwesterly on Saturday
as the high moves off to the east and this will allow high
temperatures to climb back into the low 80s. By Saturday night a low
pressure will approach and bring chances for rain and possibly
isolated thunderstorms back to the area. The cold front with this
system should move through on Sunday and then usher in below normal
temperatures again. Allblend initialization looked good and only
made minor quality control adjustments.


Aviation /discussion for 161200z taf issuance...

Issued at 651 am EDT Tuesday Sep 16 2014

Low ceilings and visibilities will hang around the sites for the
next couple of hours before slowly rising to higher end MVFR and
then scattering out to VFR by late morning/early afternoon. Sky
cover will likely stay broken throughout the day with broken
stratocu deck. Tonight cloud cover should dissipate but with light
to calm winds could see visibility restrictions develop once again.

Winds should remain northerly around 5-8 kts this morning and
decreasing in speed this afternoon and tonight.


Ind watches/warnings/advisories...


near term...jh
short term...jh
long term...cp

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