Area Forecast Discussion
Issued by NWS Indianapolis, IN

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KIND 151743
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1243 PM EST Sun Jan 15 2017

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

&&

.SYNOPSIS...
Issued at 259 AM EST Sun Jan 15 2017

Upper level energy will bring chances for a light wintry mix at
times today and tonight, then a low pressure system will bring rain
chances Monday and Tuesday. Dry weather will then return for mid to
late week next week. Temperatures will generally remain above
average through the period.

&&

.NEAR TERM.../Today/
Issued at 259 AM EST Sun Jan 15 2017

Isentropic lift will increase today, especially across the southern
forecast area, as some upper level energy moves in. Forcing is not
that impressive, but it looks to be enough to go likely PoPs for a
time this afternoon across the southwestern forecast area.

Dry air will and weaker lift will help keep the northeast forecast
area dry today (although can`t rule out a few sprinkles this
afternoon).

Temperatures will be cold enough to cause the potential once again
for some freezing rain this morning across southwestern sections of
the area. However, temperatures will be pretty close to freezing,
and road temperatures will likely be a little above freezing. With
light QPF amounts during the cold period and marginal if any icing
on roads, impacts should be limited. Will just issue a Special
Weather Statement to cover potential slick spots.

Went a little below MOS most areas and closer to a model blend given
extensive cloud cover and some precipitation.

&&

.SHORT TERM.../Tonight through Tuesday night/
Issued at 259 AM EST Sun Jan 15 2017

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

Weak lift continues tonight with some weak warm advection aloft.
Will go with mainly slight chance to low end chance category PoPs.
Precipitation type will be in question again as surface temperatures
fall below freezing again but with continued warm air aloft.

Thus freezing rain will again be possible tonight, mainly across the
north half of the area. However, low PoPs and very low QPF amounts
lead to low confidence of any impacts. Will just mention it in a
Special Weather Statement. These chances will continue into early in
the day on Monday as well before temperatures warm up everywhere.

Better chances for precipitation (all rain this time) arrive later
Monday afternoon into Monday night as a surface low and upper level
trough approach the area. Went with the initialization`s likely or
higher PoPs.

Some uncertainty on how a second upper trough evolves Tuesday and
Tuesday night, so kept the initialization`s lower PoPs during that
period.

Stayed with a model blend for temperatures.

&&

.LONG TERM /Wednesday through Saturday/...

Issued at 149 AM EST Sun Jan 15 2017

ECMWF suggests a departing short wave will have exited the area on
Wednesday...allowing strong Ridging over the Mississippi Valley
to develop and build across the Ohio Valley. By Thursday...strong
ridging aloft will be in place across the region...allowing dry
weather to persist.

ECMWF then suggests a negatively tilted short wave moving through
the Ohio Valley on Friday. A strong warm front also surges
northward across Indiana as southerly flow establishes itself
through the region. Superblend suggests dry to no pops with these
features which appears curious to this forecaster. Thus confidence
in the Friday and Friday night Period precip wise is low.

Southerly flow and ridging looks to be in place on
Saturday...allowing above normal temps which are expected through
much of this period.

&&

.AVIATION /Discussion for the 15/1800Z TAF Issuance/...

Issued at 1227 PM EST Sun Jan 15 2017

Conditions will hover right around the VFR/MVFR mark this
afternoon as visibilities struggle to improve with weak waves in
the upper flow. Conditions will only worsen through the course of
the TAF period too as a warm front and its associated low
pressure system approach from the southwest overnight. Expect
conditions to deteriorate to IFR or worse overnight/tomorrow
morning. Meanwhile, winds will generally be light and variable.

&&

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

&&

$$

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.