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Area forecast discussion 
National Weather Service Indianapolis in
425 am EDT sun Mar 29 2015


The aviation section has been updated below.


issued at 355 am EDT sun Mar 29 2015

A cold front will push through the area this afternoon and
evening...bringing showers to the area. In the wake of the
front...high pressure will provide dry weather through at least
Wednesday...when the next front will approach the area.
Thunderstorms will be possible Wednesday night through Friday.


Near term /today/...
issued at 355 am EDT sun Mar 29 2015

Cold front will push through the area late this afternoon...with
showers likely to move in to the northwestern forecast area
beginning just after midday...and overspreading the area through
the remainder of the afternoon. Duration of showers should not be
particularly long as column only saturates completely for a few
hours at most.

On temperatures...consensus numbers appeared reasonable with minor tweaks
per upstream numbers.


Short term /tonight through Tuesday night/...
issued at 355 am EDT sun Mar 29 2015

Will carry probability of precipitation into the early part of the overnight...and taper
them off quickly after 06z. Models are in general agreement that
the remainder of the short term will be dry...with only some
increased cloud cover late Monday into early Tuesday as a weak
surface wave passes north of the area.

Consensus temperature numbers appeared reasonable based on low level
thickness forecasts.


Long term /Wednesday through Saturday/...
issued at 225 am EDT sun Mar 29 2015

Mild and active extended will be in store across the the Great
Lakes...Ohio Valley and the south for the first week of April.
Models agree that the upper flow will be fast and quasi-zonal. That
in it itself lends itself to timing difficulties for the models with
the various embedded disturbances. The biggest model differences
relate to a late weekend surface wave and its strength. As far as
operational models go...the 12z European model (ecmwf) was the strongest with this
feature...while the 00z GFS was the weakest and furthest south. The
00z Canadian was more of a compromise. Meanwhile...the ensemble
means leaned towards their deterministic solutions. The majority of
the ensemble members favored a more northerly track of a surface low
albeit not as strong as the European model (ecmwf). Finally...the ewmwf and its
ensemble have been more consistent. So...prefer a solution closer to
the Euro ensemble mean...but with differences still yet to be
resolved...will not make large changes to the regional blend.

The weather prediction center surface forecasts from late last evening
suggest a warm front will lift northeast across central Indiana
Wednesday afternoon and evening. associated cold front is
expected to drop southeast across northern parts of central Indiana
Thursday night but stall somewhere nearby on Friday as a surface
wave slides northeast along the front. The front should then drop
southeast to the southern states Friday night as the wave exits
northeast. Moist southerly flow ahead of this system will allow
temperatures to rise above normal in the 60s by Thursday. It will
also serve as an ingredient for periods of showers Wednesday night
through Friday. Thunderstorms also a good bet per European model (ecmwf) instability
forecasts. Dry and cooler weather will then take over for the latter
part of the weekend.


Aviation /discussion for the 290900z ind taf update/...
issued at 425 am EDT sun Mar 29 2015

No changes needed for the taf.

Previous discussion follows...

Increasing/thickening cloud cover expected in advance of an
approaching frontal system. For the most cover should
remain above 050 through midday Sunday...although some ceilings
around 050 may move into the klaf area towards 291800z.

No visibility restrictions expected at the taf sites through midday

Surface winds expected to become 140-160 degrees at 6-9 kts towards
daybreak Sunday. Winds should veer a bit towards 170-190 degrees
with some gusts 20-25 kts probable by midday Sunday.


Ind watches/warnings/advisories...none.



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

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