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

FXUS63 KIND 240815

Area Forecast Discussion
National Weather Service Indianapolis IN
415 AM EDT SAT SEP 24 2016

The AVIATION Section has been updated below.


Issued at 252 AM EDT Sat Sep 24 2016

Dry conditions will persist through Sunday morning with ridging
aloft and high pressure centered over Ontario. However, the
pattern will change by Sunday afternoon as a low pressure system
tracks out of the Northern Plains and into Manitoba and Ontario.
This system will break down the current persistent upper ridge,
and its associated cold front will bring shower and thunderstorm
chances to central Indiana starting Sunday afternoon. Showers and
isolated thunderstorms will persist through Monday, but drier
conditions can be expected by Monday night. The dry weather will
then persist through the extended period. So, the main focus of
the extended period will be the much cooler temps with highs only
in the low to mid 70s starting Monday and overnight lows dipping
into the upper 40s/low 50s.


.NEAR TERM /Today/...

Issued at 252 AM EDT Sat Sep 24 2016

Patchy fog has formed over portions of central Indiana early this
morning and will persist through mid-morning with a weak
stationary boundary draped across the forecast area. After fog
dissipates around mid to late morning, it will turn out to be a
pleasant day with plenty of sunshine as high pressure continues to
be the predominant weather feature. High temperatures will be a
tad cooler today with highs ranging from the low 80s /northeast/
to upper 80s /southwest/ with easterly winds.


.SHORT TERM /Tonight through Monday Night/...

Issued at 252 AM EDT Sat Sep 24 2016

The main focus of the short term period will be
shower/thunderstorm chances on Sunday and Monday with a cold
front, as well as cooler temperatures.

Dry conditions will prevail through tomorrow morning due to
ridging aloft and high pressure over Ontario. The pattern will
start to change by tomorrow though as a low pressure system slides
out of the Northern Plains and into Manitoba. Its associated cold
front will start impacting central Indiana after Sun 18Z. Shower
and thunderstorm chances will increase from west to east
throughout the day on Sunday. Best forcing with aforementioned
front/isentropic lift is expected to fall between the Mon 06Z-
18Z time frame. So, will continue to carry mention of likely pops
at times from west to east through that time period.

Low precip chances will linger through Monday afternoon, but do
not expect much in the way of residual rain with upper low. So,
trended toward a dry forecast by Monday evening.

The other area of focus in the short term period will be the shift
to more Fall like temperatures by Monday as daytime highs only top
off in the low to mid 70s. And, as skies clear out on Monday
night, radiational cooling will result in lows dipping into the
upper 40s/low 50s, some of the coolest in awhile.


.LONG TERM (Tuesday through Friday)...

Issued at 203 AM EDT Sat Sep 24 2016

The initialization from Region will be used.

Confidence is high the period will be dry, with all models
agreeing about that.

There is not good agreement about how much cold air will come south
Tuesday and Wednesday, with the European model considerably warmer
than the GFS.As a result, errors of 2-3 degrees or so are
possible in the forecast that will be issued today.

Potential errors drop to around 2 degrees Thursday and 1 degree
Friday as the models come into alignment with how fast warmer air
will return.


.AVIATION (Discussion for 240900Z TAF update)...

Issued at 415 AM EDT Sat Sep 24 2016

Conditions will vary widely early as a weak front causes areas of
stratus.  Expect mostly mvfr ceilings and visibilities, with areas
of ifr visibility.  The stratus should burn out during the morning,
with ceilings rising to about 4 feet and visibilities becoming
greater than 6 miles.

Winds will be mostly from the east at 7 knots or less.


.IND Watches/Warnings/Advisories...


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