Area Forecast Discussion
Issued by NWS Indianapolis, IN

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FXUS63 KIND 251324

Area Forecast Discussion
National Weather Service Indianapolis IN
824 AM EST Sat Feb 25 2017

The NEAR TERM Section has been updated below.


Issued at 256 AM EST Sat Feb 25 2017

The fluctuating pattern will continue as cooler temperatures
prevail through the weekend, quickly followed by a warm-up early
next week. First, light snow showers will persist this morning in
wraparound moisture on the back side of yesterday`s system.
However, high pressure will quickly strengthen over the region by
this afternoon, resulting in dry conditions through Sunday. At
that point, precipitation chances will increase again as the first
of several disturbances enters central Indiana.


.NEAR TERM /Rest of Today/...

Issued at 816 AM EST Sat Feb 25 2017

Snow showers moving through the area currently have been a little
more intense in terms of visibility reductions and quick
accumulations, so increased pops a bit and included a tenth or two
of accumulation across much of the area. Impact to roads should be
minimal with warm road temperatures, and warm ground temperatures
should also mean that melting of that couple of tenths should
occur pretty rapidly once the heavier showers move out. With most
surface temps near/below freezing and warming not expected seeing
snow as the precip type, with only brief reports of rain mixing in
over southern counties before they turn to snow/flurries.

Most intense showers are over the eastern half of the area and
rapidly moving east. Still seeing flurries back over central
Illinois, so for now carried them through noon but may need to
extend that. Winds of 15 to 25 mph with gusts around 35 mph will
produce wind chills through the day in the teens.


.SHORT TERM /Tonight through Monday Night/...

Issued at 256 AM EST Sat Feb 25 2017

The main focus of the short term period will be 2 rounds of
precipitation, the first starting Sunday night and the second
beginning on Monday night.

High pressure/zonal flow will result in dry conditions tonight
through tomorrow. However, moisture will start increasing from the
south on Sunday night ahead of the next upper trough.
Precipitation will initially start out as rain tomorrow evening
across the southern counties, but it could transition to a wintry
mix overnight as temperatures drop. This wintry mix will spread
into the central and northeast counties by daybreak Monday and
quickly transition back to all rain before ending early Monday
afternoon.  No snow accumulations are expected.

After a short period of dry conditions on Monday afternoon, rain
will quickly re-develop on Monday evening ahead of the next
system approaching from the west. Latest Superblend initialization
is trending toward likely pops by Monday night, which seem
reasonable as the system moves closer.

A gradual warming trend will prevail through the period with highs
in the low to upper 40s on Sunday and low/mid 50s by Monday.
Meanwhile, overnight lows will jump from the 30s on Sunday night
to 40s on Monday night. Did not need to deviate from latest
Superblend initialization.


.LONG TERM /Tuesday through Friday/... Issued at 245 AM EST Sat
Feb 25 2017

Forecast confidence will start off good as models agree that a cold
front will move east across central Indiana Wednesday. Deep moisture
advected in off the Gulf ahead of the system, along with waves
moving along the front, suggest high pops per the Superblend are a
good bet. In addition, operational 00z GFS and ECMWF both have
decent instability Tuesday through Wednesday. So, have thunder in
the grids in that time period. Kept shower chances in through
Wednesday night, as a trailing upper trough moves through. Could see
some snow mix in overnight across our northern counties as the
roller coaster weather continues.

Less confidence the remainder of the long term as models handle the
next system differently. The 00z has a well defined frontal system
moving through the area Thursday night. The 00z ECMWF has much less
of a surface reflection. However, both have an cyclonic flow over
the area, so small superblend pops are justified Thursday night.
Left small pops in the extreme northeast Friday morning as the
system moves out. Could once again see some snow mix in, mainly over
the northeastern half. Accumulation is not expected at this time.

Superblend looks to be handling the temperature trends well, so no
reason to make any changes. Highs could once again reach the 60s on
Monday with highs in the 40s to follow late week.


.AVIATION /Discussion for the 25/12Z TAF Issuance/...

Issued at 626 AM EST Sat Feb 25 2017

Wraparound snow/rain showers will keep conditions at MVFR/IFR
levels this morning due to reduced visibilities and ceilings.
However, VFR conditions should return by early afternoon as high
pressure strengthens over the region. Winds will remain strong out
of the west with sustained speeds of 10 to 15 kts, gusting to 28
kts through this evening.




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