Area Forecast Discussion
Issued by NWS Indianapolis, IN

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FXUS63 KIND 161430

Area Forecast Discussion
National Weather Service Indianapolis IN
930 AM EST Tue Jan 16 2018


The Aviation section has been updated below.


Issued at 220 AM EST Tue Jan 16 2018

Arctic air will remain entrenched over central Indiana through
Wednesday. Then, temperatures will warm to well above normal this
weekend. A frontal system will bring rain to the area, especially
Sunday night and Sunday night. A mix with snowflakes is possible by


.NEAR TERM /Today and Tonight/...
Issued at 620 AM EST Tue Jan 16 2018

Updated to lower minimum wind chills to 20 below per latest

Previous discussion follows...
Issued at 220 AM EST Tue Jan 16 2018

The main weather impact today, and especially this morning, will be
the cold with wind chills to around 15 degrees below zero at times.
Thus, a borderline Wind Chill Advisory will remain in effect through

Also, there could be some flurries or light snows around today and
tonight as energy rotates around an elongated Great Lakes upper low
and through central Indiana. Could see snow showers with slightly
more intensity over northern sections due to Lake Effect off Lake

Blend temperatures look reasonable. Moderate confidence temperatures
will start off around zero degrees at daybreak and only top out from
around 10 to 15 degrees late today. It will not be quiet as cold
tonight with lows in the single digits above zero and wind chills as
low as 8 degrees below zero.


.SHORT TERM /Wednesday through Thursday night/...
Issued at 220 AM EST Tue Jan 16 2018

The main focus for the short term will be on temperatures.

Wednesday will start off with the former elongated upper low opened
as a trough and southeast of central Indiana. Meanwhile, surface
high pressure will be over the Ozarks and southern Plains. This high
will drop to the southern states by Thursday and allow a dry
southwest flow of air into the Ohio Valley and Great Lakes. Also
noticeable will be increasing sunshine Wednesday with little cloud
cover thereafter.

Regional blend has temperatures closer to normal by Thursday, which
looks reasonable with the limited cloud cover and southwest flow.


.LONG TERM /Friday through Monday/...
Issued at 225 AM EST Tue Jan 16 2018

Ensembles suggest a progressive upper pattern across the area
during this period. Upper ridging over the Ohio Valley over the
weekend will give way to an upper trough that is expected to move
into the Midwest by early next week.

At this time, there are the usual differences among the individual
members as to the timing and intensity of the surface system
associated with the upper trough. However,there is good agreement
that the dominate precipitation type will be rain, with the only
threat for mixed precipitation being on Monday at the tail end of
the event. Will go with PoPs from Saturday to Monday to cover this


.AVIATION /Discussion for the 161200Z TAFS/...
Issued at 930 AM EST Tue Jan 16 2018

Added earlier MVFR to LAF and IND as area of snow showers and lower
cloud progresses southward this morning. Previous discussion follows.

Issued at 540 AM EST Tue Jan 16 2018

Short term model guidance suggests that extensive MVFR ceilings
015-030 over the southern Great Lakes will overspread the
terminals from north to south during the day today, reaching the
southern terminals by the early afternoon hours.

An upper level disturbance moving through today may result in
scattered flurries or light snow showers in the vicinity of the
terminals from about midday through the afternoon hours. Any
visibility restrictions associated with the showers should be
brief and localized.

Surface winds generally 250-270 degrees at 8-12 kts.



Wind Chill Advisory until noon EST today for INZ021-028>031-



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