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Area forecast discussion 
National Weather Service Indianapolis in
640 am EDT Monday Mar 30 2015


The aviation section has been updated below.


issued at 400 am EDT Monday Mar 30 2015

High pressure will keep weather quiet across the area today. A
very weak wave will pass north of the area Monday night into
Tuesday...which will only lead to a temporary increase in cloud
cover as precipitation appears unlikely. Developing low pressure
later in the week may be able to provide chances for showers and
perhaps a few thunderstorms as early as Wednesday night and
continuing through Friday night.


Near term /today/...
issued at 400 am EDT Monday Mar 30 2015

Quiet day on tap across central Indiana in the wake of overnight
frontal passage. Upped cloud cover this afternoon as forecast
soundings indicate convective temperatures are likely to be
reached. In addition...increasing middle and high cloud expected
ahead of system to skirt north of the area Monday night into Tuesday.

On quibble with consensus numbers which track fairly
well with upstream numbers.


Short term /tonight through Wednesday night/...
issued at 400 am EDT Monday Mar 30 2015

Models agree on keeping the short term dry through at least
Wednesday. GFS is a bit more aggressive than Euro in bringing
convection into the area Wednesday night...and will carry some
slight chance probability of precipitation then...but more substantial probability of precipitation are best left
for later periods. K index values indicate some potential for
thunder if any precipitation does occur Wednesday night.

Consensus temperature numbers appeared reasonable with a few minor
tweaks. Will be quite a bit milder during the period in
comparison with recent days.


Long term /Thursday through Sunday/...
issued at 340 am EDT Monday Mar 30 2015

Deterministic models have some timing issues...namely with waves
riding northeast along a frontal boundary Friday and Friday night.
Otherwise...the 00z GFS and European model (ecmwf) are much closer than previous runs
which had the ecwmf much stronger with a primary surface wave...and
the GFS much further south with weaker waves. In addition...a blend
is not too far off from ensemble means. The 00z Canadian...on the
other hand...looks too slow and too far south. So...prefer a non-Gem

The extended should start off active as a frontal system moves to
the western Great Lakes and Southern Plains Thursday morning. The
front will then drop southeast over central Indiana before stalling
near the Ohio River Thursday night as the previous discussed surface
waves ride up along the front. With return flow ahead of the frontal
system...good chance to likely probability of precipitation look good on Thursday along with
above normal temperatures in the 60s to lower 70s per the regional
blend. Likely probability of precipitation continue to look good across our southern
counties Thursday night...with the frontal stalling out. In
addition...instability forecasts warrant thunder chances.

The front should slide southeast of the area on Friday and Friday
night as the waves pass to the east. However...likely probability of precipitation continue
to look good on Friday tapering off to chance probability of precipitation northeast. Will
also leave in chance probability of precipitation Friday night as an upper wave moves across
in the fast zonal flow. High pressure will then build in during the
remainder of the weekend...which should bring mostly dry weather
with near or slightly below normal temperatures with afternoon highs
in the 50s...except in the lower 60s Sunday south.


Aviation /discussion for 301200z taf issuance/...
issued at 640 am EDT Monday Mar 30 2015

VFR conditions expected through the taf period with just some high
and middle PM clouds.

Winds will be northwest around 10 knots this afternoon with gusts to
15 knots or so.


Ind watches/warnings/advisories...none.



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

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