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Area forecast discussion 
National Weather Service Indianapolis in
1240 am EDT Wednesday Apr 16 2014

Update...
the aviation section has been updated below.

&&

Synopsis...
issued at 345 PM EDT Tuesday Apr 15 2014

An upper trough is clearing the area and surface high pressure is
building into the area this evening. Temperatures will likely drop
well into the 20s across the area tonight under very light winds
and clearing skies. Dry weather will continue through at least
Thursday before a system may bring some showers to the area late
in the week and over the weekend. Fortunately...temperatures will
also moderate back to much closer to normal for the time of year.

&&

Near term /rest of tonight/...

Issued at 1002 PM EDT Tuesday Apr 15 2014

0200z update...really only needed to make a few minor
modifications to forecast based on latest trends this evening.
Previous discussion follows.

The winter that refuses to die brought US one last /hopefully/
parting shot today...with lake effect snow showers...some
convective flurries...and a daily record low maximum temperature at
Indianapolis that will likely blow the old record of 40 degrees
out of the water. Although echoes still remain on the radar...very
little if any is making the ground owing to rapidly increasing
surface dewpoint depressions as gusts and subsidence associated
with the approaching surface high have helped to bring down drier
air to the surface. Will keep a pre first period mention of
flurries or snow showers for the next few hours however with these
echoes remaining in the area.

As the high continues to build into the area...skies will clear
and winds will go light to calm. This will allow temperatures to
drop easily overnight...and went with the cooler MOS blend over
other guidance...which brings temperatures down well into the 20s across
the area.

&&

Short term /Wednesday through Friday/...
issued at 345 PM EDT Tuesday Apr 15 2014

Dry weather with high pressure will continue through at least
Thursday. An approaching weak frontal system and upper wave will
necessitate at least low probability of precipitation Thursday night and Friday across
much of the area...but at this time instability is low per model k
index values...so will only mention showers.

Temperatures will quickly moderate in part thanks to the time of
year...and temperatures should return to near normal toward the end of
the period. Patchy frost may be a concern for one more day across
the southeastern counties which have begun the growing
season...but after what looks like a hard freeze tonight this may
not be a major concern. Consensus numbers appeared reasonable with
a few minor tweaks.

&&

Long term /Friday night through Tuesday/...
issued at 240 PM EDT Tuesday Apr 15 2014

Showers will be in the process of departing off to the east Friday
night as the upper wave and weak surface low move away from the
region. A surface ridge will then move across the Great Lakes and
Ohio Valley with dry weather into early Sunday. Another broad upper
wave with a weak frontal boundary at the surface will track through
the Ohio Valley by early next week. Model guidance offering variance
with respect to timing and track of the system...so deviated little
from allblend and will maintain chance probability of precipitation Sunday and Monday. High
pressure returns for Tuesday with a large upper ridge expanding east
into the region for midweek. Highs will be seasonable through the
period...generally rising into the 60s.

&&

Aviation /discussion for 160600z taf update/...

Issued at 1240 am EDT Wednesday Apr 16 2014

VFR expected through the period. Gusty winds return middle morning
through the afternoon.

Scattered to broken middle and high clouds will move through during the
period.

Winds will pick up again middle to late morning...with gusts over 20kt
likely from 14-16z through the afternoon. Winds will diminish by 00z.



&&

Ind watches/warnings/advisories...
freeze warning until 10 am EDT Wednesday for inz060-061-067>072.

&&

$$

Synopsis...nield
near term...smf/nield
short term...nield
long term...Ryan
aviation...50/cp

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