Area Forecast Discussion
Issued by NWS Indianapolis, IN

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210
FXUS63 KIND 161911
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
212 PM EST Mon Jan 16 2017

.UPDATE...
The LONG TERM Section has been updated below.

&&

.SYNOPSIS...
Issued at 315 AM EST Mon Jan 16 2017

A series of low pressure systems will bring rain chances to central
Indiana at times into the weekend. Temperatures will remain above
normal through the next week.

&&

.NEAR TERM.../Today/
Issued at 315 AM EST Mon Jan 16 2017

Only weak lift is expected this morning with a warm front well to
the south. However wouldn`t rule out an isolated shower or patchy
drizzle, so will go slight chance PoPs during much of the morning
across the forecast area. With temperatures expected to be near
freezing across the far northern forecast area at 12Z, will
including a brief mention of freezing rain early in the day.

Some of the hi-res short term models as well as the LAMP show some
lower visibilities in fog this morning. HRRR shows widespread 1/4
mile visibility moving in during the morning, but it`s overdoing the
extent of low visibility at the current hour. Will add patchy fog
mention for now and continue to watch.

The warm front will move close to the southern forecast area by 00Z.
Isentropic lift will increase, and 850mb winds will increase as
well, bringing in forcing and moisture. HRRR shows rain moving into
most of the area by 00Z, but this seems a bit fast.

Will increase PoPs through the afternoon, with about the western
half of the area seeing likely PoPs by 00Z, with chance PoPs
elsewhere.

Went closer to the MAV MOS for highs today, which looks more
reasonable than the warmer MET given expected arrival of warm front
and plenty of cloud cover. Daytime highs will occur late in the day.

&&

.SHORT TERM.../Tonight through Wednesday night/
Issued at 315 AM EST Mon Jan 16 2017

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

Rain will overspread the area tonight with first the warm front
moving through during the evening and then a cold front moving into
the area late in the night. 850MB winds of 40kt and the approach of
an upper jet will aid in the forcing. Went categorical PoPs all
areas. There could be a brief lull after the warm front passes and
before forcing from the approaching cold front gets here.

Some instability will move into the area during the night, so
continued the mention of thunder.

Temperatures may dip a couple of degrees early in the night, then
they should rise through the remainder of the night.

The cold front will move through Tuesday morning, but the better
forcing will be east of the area. Kept the initialization`s chance
PoPs. Low PoPs will continue some areas into Tuesday night as an
upper trough moves through.

High pressure will then build in and provide dry weather.

The cold front will not have any strong push of cold air behind it,
so temperatures will continue to be above normal into Wednesday.

&&

.LONG TERM /Thursday night through Monday/...
Issued at 212 PM EST Mon Jan 16 2017

A mild and wet period is on tap this weekend and early next week.

Deterministic models are now in pretty good agreement over 3 main
upper systems that will effect central Indiana. So, with some
confidence, expect the first of these systems to bring widespread
showers to the area Thursday night into Friday. This system is
currently over Mexico and the four corners region and will
eventially become negatively-tilted as it pinwheels northeast over
the Ohio Valley on Friday and spins up a surface low and occluded
front. Instability progs suggest thunder is not out of the question.

Models then pivot another southwestern system northward on Saturday.
However, this one will be west of the first one, across the Plains.
This, should keep the forecast area mostly dry until Saturday night.
Then the final system is progged to wind up over the Ohio Valley
Sunday night into Monday. More widespread showers and possibly
thunderstorms are expected with this system.

Regional blend pops looked good except after coordinating with LMK,
PAH and ILX, pulled small blotchy pops associated with the second
system on Saturday.

With southerly flow off the Gulf, temperatures will be well above
normal with highs in the 50s and possibly 60s per Regional blend.

&&

.AVIATION /Discussion for the 16/1800Z TAF Issuance/...

Issued at 1226 PM EST Mon Jan 16 2017

Poor flying conditions are expected for duration of TAF period as
a warm front draws moisture into the area. IFR or worse will be
the prevailing flight categories for most of the TAF period with
just slight improvement toward the end when MVFR conditions return
tomorrow morning. Winds will generally be southeasterly, gradually
veering to the southwest tomorrow morning. Sustained speeds will
range between 5 to 11 kts.

&&

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

&&

$$

SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....MK
AVIATION...TDUD



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