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Area forecast discussion 
National Weather Service Indianapolis in
605 am EST sun Feb 14 2016

the aviation section has been updated below


issued at 334 am EST sun Feb 14 2016

Central Indiana will be under an active weather pattern through
next week as a series of disturbances move through the region. The
first will start impacting the area this morning...resulting in 1
to 3 inches of snowfall by tonight across central Indiana. The
second disturbance will pass through on Monday...but rain mixing
in will limit snow accumulations. Yet another system will bring
mixed precipitation on Tuesday. Further out...a warm up can be
expected during the extended period with rain chances on Friday.


Near term /today/...
issued at 334 am EST sun Feb 14 2016

The main focus of the near term period will be snow chances with
upper trough.

Current reports and radar mosaic indicate light snow falling
across portions of central Illinois. As lower levels become
saturated this morning...snow will become more widespread and
should start entering the western portions of central Indiana
around sun 10z.

Snow will continue to spread east through the course of the day
with the best isentropic lift during the sun 18z-Monday 00z. This
will be when highest amounts are accumulated...expecting between 1
to 3 inches of snow. Will continue with Winter Weather Advisory
over all of central Indiana except the northeast quadrant through
midnight EST tonight. Advisory will go into effect across central
portions of the forecast area at 8 am EST Sunday...and 3 hours
earlier across the western counties.


Short term /tonight through Tuesday night/...
issued at 334 am EST sun Feb 14 2016

The main focus of the short term period will be the remnants of
the first system followed by another disturbance on Tuesday.

Isentropic lift abruptly cuts off across central Indiana after Monday
03z as moisture decreases. So...rapidly decreased probability of precipitation from west
to east after sun 06z with just a few additional tenths of an inch
of snow accumulation overnight.

Focus then turns to the next upper wave prognosticated to move through on
Monday evening. Expect a lull in activity on Monday afternoon with
just a brief spike in precipitation on Monday evening as that
upper wave moves through...but moisture appears limited. So...will
only go with slight chance probability of precipitation for Monday evening and night.

Finally...a third disturbance will track across the area on
Tuesday. This will be more of a mixed precipitation event though
as temperatures top off in the upper 30s/low 40s on Tuesday
afternoon. As cooler air moves in on Tuesday night...the northern
half of central Indiana will see a turn over to snow...while
southern portions can expect a rain/snow mix. During the day on
Tuesday...northern portions will see a rain/snow mix...while the
southern counties will receive mainly rain.


Long term /Wednesday through saturday|/...
issued at 309 am EST sun Feb 14 2016

Primary focus through the extended period will be a February thaw
as the broad upper ridge over the western part of the country
finally shifts east. Temperatures will surge to above normal
levels by Friday and continuing into the weekend.

The Ohio Valley will remain in a cool cyclonic flow aloft on
Wednesday as the upper trough slowly shifts away to the east . Not
out of the question to see lingering flurries or very light snow
showers in this setup...but will leave dry at this time with
surface high pressure asserting its influence by late day.

The high will shift across the Great Lakes and into New England
by early Friday. At the same time...strong low pressure will
develop over the northern plains then move east into the Great
Lakes by Friday. A strong S/SW flow will develop between the high
to the east and the low to the northwest...resulting in windy
conditions on Friday and much warmer temperatures as strong warm
advection develops ahead of the associated cold front. Scattered
rain showers will accompany the passage of the cold front late
Friday. Dry weather will return on Saturday with high pressure
before another system brings precipitation for late weekend.

Highs will rise into the 50s to near 60 by Friday...remaining
above normal in the upper 40s to middle 50s over the weekend.


Aviation /discussion for 141200z taf issuance/...
issued at 605 am EST sun Feb 14 2016

Poor flying conditions developing in snow...especially this
afternoon and evening.

Moisture steadily expanding into central Indiana early this
morning but soundings show dry air remains within the boundary
layer. As lift strengthens through the morning it will aid low
level saturation with light snow developing across the terminals.
Any restrictions should remain in the MVFR category this
morning...although both kbmg and khuf may see brief drops in snow
to IFR.

Much stronger isentropic lift will arrive by early afternoon in
advance of a vigorous wave aloft. Combined with frontogenetical
forcing in the middle levels...expect a 3 to 6 hour period with
moderate to occasionally heavy snow from the afternoon into the
evening with LIFR and lower conditions expected. Hi-res guidance
shifts the band of widespread heavier snow to our east during the
evening but presence of forcing in the middle levels courtesy of the
wave aloft should enable scattered snow showers into the
overnight with periodic IFR restrictions. Snow showers are likely
to diminish in the predawn hours but MVFR stratus will linger
through the end of the forecast period.

Southeast winds at 10 to 15kts through the day will gradually veer
to southerly overnight and diminish after midnight.


Ind watches/warnings/advisories...
Winter Weather Advisory until midnight EST tonight for inz029-

Winter Weather Advisory until midnight EST tonight for inz028-



near term...tdud
short term...tdud
long term....Ryan

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