000
FXUS63 KIND 181025
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
525 AM EST Mon Feb 18 2019

.UPDATE...
The AVIATION section has been updated below.

&&

.SYNOPSIS...
Issued at 351 AM EST Mon Feb 18 2019

Some very light snow and flurries this morning combined with some
black ice from freezing drizzle yesterday evening could create
some hassles for the morning commute across central Indiana. High
pressure will bring brief dry weather, but another system arriving
Tuesday night will again bring several types of precipitation to
the area before it exits Wednesday night. Rain then arrives in
time for the weekend.

&&

.NEAR TERM /Early this morning and Today/...

Issued at 351 AM EST Mon Feb 18 2019

Seeing some light snow on radar early this morning across some spots
in the northern counties, with weak echoes central that at this
time aren`t producing anything that`s reaching the ground, and
some patchy light drizzle/freezing drizzle across a few of the
southern counties. The surface trough producing this precip is
going to slowly move away from the area today, and thus will keep
some chance PoPs into the morning across the northern counties
closest to the forcing. Think most areas will see little to
nothing in the way of accumulation, and transition to chances for
flurries by mid morning that could last into the afternoon, again
across the northern and central counties where the surface trough
is set up. The upper cyclonic flow will help to keep these off and
on flurries going, but by late afternoon upper ridging should
build in enough to shut them off.

As far as impacts are concerned, expect to see slick spots this
morning, especially on bridges, overpasses, and untreated roads
from the period of freezing drizzle last night as well as the
flurries/light snow early this morning creating some black ice.
Will keep SPS going for this through the morning commute time.

&&

.SHORT TERM /Tonight through Wednesday night/...

Issued at 351 AM EST Mon Feb 18 2019

Upper ridging and surface high pressure will bring dry conditions to
central Indiana for tonight through Tuesday. Tuesday evening an
upper wave swings out of southwesterly flow toward the area,
bringing good forcing and moisture with it. This will bring
precipitation to the area Tuesday night and Wednesday, with the
precipitation changing over to rain from south to north during the
morning. Better confidence on the changeover and timing of
precipitation than there is on precip type for Tuesday night
though. At this time it looks like the column will be cold enough
for snow at onset, but models are indicating potential for strong
warm advection aloft which could cause a transition to freezing
rain. Some model differences regarding how quickly this warm
advection will arrive as well as how long it will take for the
surface to warm above freezing. At this time shooting for a middle
of the road solution with some light icing and snowfall amounts
around 1 to 2 inches across the area. Some potential for banding
could exist and will have to keep an eye on this going forward.

&&

.LONG TERM (Thursday Through Sunday)...
Issued at 250 AM EST Mon Feb 18 2019

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

Central Indiana will remain in between an upper trough to the west
and an upper ridge off of the southeast coast of the USA through the
end of the work week. Although some energy moves through the flow,
the trend has been for precipitation to stay farther south. Thus
will keep Thursday and Friday dry.

For the weekend, the upper trough will eject northeast, and a strong
surface low looks to develop. Models continue to disagree a bit on
the details, but they are close enough that the blend`s higher PoPs
Saturday and Saturday night look reasonable. Lower PoPs will linger
into Sunday as the system exits.

Temperatures will remain above normal for most of the period, with
Saturday having the potential to be well above normal depending on
the track of the surface low and the amount of rain with it.

&&


.AVIATION (Discussion for the 181200Z TAF Issuance)...
Issued at 525 AM EST Mon Feb 18 2019

MVFR conditions are expected through much of the daylight hours
today, then VFR conditions will return by this evening.

MVFR ceilings with scattered snow showers will be the rule early
this morning. Mainly scattered flurries with no visibility
restriction are expected after 15Z. (Can`t rule out some brief
periods of VFR at times with holes in the MVFR ceiling this morning).

Ceilings will lift late this afternoon and then scatter out this
evening so that the night will be VFR.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...CP
NEAR TERM...CP
SHORT TERM...CP
LONG TERM...50
AVIATION...50