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fxus63 kind 261834 

Area forecast discussion
National Weather Service Indianapolis in
234 PM EDT sun Mar 26 2017

the long term section has been updated below.


issued at 310 am EDT sun Mar 26 2017

A few low pressure systems will move through central Indiana during
the next week, bringing frequent chances for showers and some
thunderstorms to the area. Temperatures will remain near to above
average into next weekend.


Near term.../today/
issued at 310 am EDT sun Mar 26 2017

Rain was falling across much of central Indiana early this morning,
thanks to upper and surface lows back near the Mississippi River.

The lows will move into lower Michigan by this evening. The current
widespread rain should shift east some by morning, but latest hi-res
models indicate that the northeastern 2/3 of the area should still
be seeing rain. Will go categorical pops northeast half tapering to
chance pops southwest at the start of the today period.

This first band will continue to shift off to the east during the
morning, but the hi-res models as well as ensembles show another
round of rain developing midday as a surface front moves through and
an upper jet moves in. This will bring more likely pops to the area.
Will try to time a break between the areas of rain where possible.

Pops will then diminish west to east during mid afternoon to early
evening as the system begins to exit the area.

There will be some instability so will continue with a thunder

Went a little above the model blend for high temperatures most areas
based on latest performance.


Short term.../tonight through Tuesday night/
issued at 310 am EDT sun Mar 26 2017

Models are close enough that the model blend initialization
was accepted for most items.

Will include some low pops this evening east to account for any
lingering rain from the existing system. The area should remain in
between systems overnight, so continued a dry forecast then.

An upper trough and another surface low will move in for Monday and
Monday night. Again with this system moisture and forcing look good.
Will go likely or higher pops most areas by Monday afternoon and
across all areas Monday evening.

Based on the expected path of the surface low, it looks like
sufficient shear and instability will work into the southern half or
so of the forecast area for the potential for a few severe storms
Monday afternoon and evening. Thus the Storm Prediction Center has
placed parts of the area in a marginal and slight risk for this

Kept some low pops Tuesday as the system exits, then dry weather
should return.

The model blend temperatures look OK through the period given the
expected path of the system. Will have to keep an eye out on Tuesday
though as some models indicate colder air than the blend suggests
working into the northwest forecast area.


Long term /Wednesday night through Sunday/...

Issued at 234 PM EDT sun Mar 26 2017

A pair of systems will bring the threat for showers to central
Indiana late next week and early next weekend as well as late next

Models in general agreement that a Pacific system will strengthen
over rockies and move into the Southern Plains and northeast across
the Ohio Valley and lower Great Lakes next Friday. Then after brief
ridging on Saturday, another Pacific system will move into the
plains on Monday. A moist and unstable flow off the Gulf and ahead
of advancing cold front, combined with the synoptic scale forcing,
favor high pops Thursday into Friday morning. Left in lingering
chance pops through Friday night as a buffer. Then, chance pops look
reasonable by Sunday afternoon as the second system gets closer and
more Gulf moisture advects northward ahead of it.

Instability progs suggest thunder is a possibility with the first
system but probably not with the start of the second.

Low level thermal progs and expected cloud cover support the
slightly above normal temperature blend output from forecast builder
with highs in the upper 50s to mid 60s.


Aviation /discussion for the 26/1800z taf issuance/...

Issued at 132 PM EDT sun Mar 26 2017

Conditions will fluctuate around the MVFR/VFR mark through the
afternoon hours as showers linger across central Indiana. There
could even be brief periods of IFR conditions in heavy rain
showers. As the system pushes farther east this evening, there
will be improvement and a trend back toward VFR conditions as the
area falls between two systems. Winds will start out southwesterly
and then eventually become southeasterly late in the period at 5
to 11 kts.


Ind watches/warnings/advisories...none.



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