Area Forecast Discussion
Issued by NWS Indianapolis, IN

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 081644
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1144 AM EST Thu Dec 8 2016

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

&&

.SYNOPSIS...
Issued at 304 AM EST Thu Dec 8 2016

Colder air will continue to flow into central Indiana into the
weekend. A low pressure system will bring a wintry mix of
precipitation to the area for the second half of the weekend into
early next week. Another shot of even colder air will move in by mid
week next week.

&&

.NEAR TERM.../Today/
Issued at 1126 AM EST Thu Dec 8 2016

Added flurries to all but the far southern counties per radar and ob
trends.

Previous discussion follows...
Issued at 304 AM EST Thu Dec 8 2016

Cold advection will continue through today, and an upper trough will
impact locations mainly north of the area.

As the colder air continues to flow in today, expect stratocumulus
to overspread much of the area by late afternoon. Models aren`t
doing great with the areas of lower cloud across the area now, so
confidence is low in timing of the arrival of the lower clouds.

Temperatures will not do much today with the cold advection and
lower clouds moving in, so stuck with the model blend which puts
highs in the 20s most areas. Wind chills could be in the single
digits at times today.


&&

.SHORT TERM.../Tonight through Saturday night/
Issued at 304 AM EST Thu Dec 8 2016

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

Tonight should see mostly cloudy conditions for much of the area as
the colder air continues to move in. Wouldn`t be too surprised to
see a few flurries across parts of the area, but at the moment am
not confident enough to add. Single digit wind chills will be across
the area tonight into Friday morning.

Partly to mostly cloudy skies will rule Friday into Saturday, but
high pressure at the surface will keep conditions dry.

Saturday night warm advection aloft and perhaps some additional
forcing from an upper jet to the north will allow for chance PoPs
across the area, especially after midnight. Forecast soundings show
snow will remain the precipitation type.

Stayed with the blend for temperatures.

&&


.LONG TERM.../Sunday Through Wednesday/
Issued at 304 AM EST Thu Dec 8 2016

Ensembles in fairly good agreement with the major details during
this period. Rather zonal flow early in the period will tend towards
some amplification of a trough over the eastern parts of the country
by the middle of next week. Despite the overall agreement on the
main details, there are significant differences among the ensembles
with respect to the finer details, lending to a lower confidence
forecast.

Appears a short wave trough will be passing over the area early in
the period. There are still large differences as to the track and
intensity of the associated surface system, and whether there will
be secondary development along the trailing front. Overall, trends
suggests a weaker surface system, but a better potential for a
secondary low on Sunday and Sunday night. Will keep PoPs in the
forecast from Saturday night through Monday morning to cover this
system. Given the weaker surface system, the push of warmer air may
be weaker as well.

Ensembles still suggest enough warm air may get into the system for
mixed precipitation at times on Sunday and Sunday evening.
Accumulating snows probable from Saturday night into Sunday night.

The next trough expected to pass through the area around next
Tuesday and Wednesday may end up being the stronger of the two,
since this one has a better chance of amplifying the flow. Will go
with chance PoPs for snow by next Tuesday and Wednesday for now, but
if this system trends stronger, precipitation types may become an
issue.

&&


.AVIATION (Discussion for the 081800Z TAF Issuance)...
Issued at 1144 AM EST Thu Dec 8 2016

Based on radar and GFS LAMP, moderately confident that MVFR ceilings
will continue for the bulk of the time through Friday morning.

Could see WNW winds gust to near 25 knots this afternoon and stay
up around 10 knots after 23z.

&&

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

&&

$$

SYNOPSIS...50
NEAR TERM...50/MK
SHORT TERM...50
LONG TERM...JAS
AVIATION...MK



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