Area Forecast Discussion
Issued by NWS Indianapolis, IN

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
FXUS63 KIND 281858

Area Forecast Discussion
National Weather Service Indianapolis IN
258 PM EDT Wed Sep 28 2016

Long term section has been updated below.


Issued at 1257 PM EDT Wed Sep 28 2016

An extremely slow moving low pressure system will stay close to
Indiana until Sunday. A high pressure system should traverse our
state from east to west Monday through Wednesday.


.NEAR TERM (Tonight)...

Issued at 1257 PM EDT Wed Sep 28 2016

The main issue is POPs.

There is extremely good model agreement about a upper low pressure
staying over the area.  This could cause convection, but nighttime
cooling should make the chance lower than during the day.

There are notable differences in the POP guidance. For instance the
MAV has likely in places where the MET has chance and visa versa.
With no model clearly better in the deterministic fields, a
consensus forecast is best so the CONSALL POP will be used.

Rain or not, the night will be mostly cloudy due to the low aloft.

Background deterministic fields and statistical guidance are all
very close with temperatures, and all support using a consensus.


.SHORT TERM (Thursday through Saturday)...

Issued at 1257 PM EDT Wed Sep 28 2016

The models agree in maintaining low pressure over the area both at
the surface and aloft. Rain chances are the main forecast issue.

With the low pressure around, this will be a cloudy spell with the
rain chances being controlled by relatively subtle features
difficult to forecast. This means consensus POPs should be
superior overall.

The fields controlling temperatures are similar between the models.
Exact values will be sensitive to if and when rain falls. Breaks in
clouds, even if brief, would also have a significant impact on
temperatures. All this indicates consensus will be the best
forecast, with possible errors of 2-3 degrees.


.LONG TERM /Saturday Night through Wednesday/...
Issued at 258 PM EDT Wed Sep 28 2016

The upper low which will bring us cool and showery weather through
Saturday will move on to the east early next week. An upper ridge
will temporarily build across Indiana Monday and Tuesday before
another system starts to move our way later next week.

Will continue low chances of showers over northeast sections
Saturday night and Sunday.  But the rest of the long term
period will be mostly dry with high pressure in control.  An
approaching frontal system may bring a slight chance of showers
western sections late Wednesday and to all areas by Thursday.

Temperatures will become warmer by the middle of next week with
highs approaching 80 Tuesday and in the lower 80s some areas
Wednesday.   Lows ill be in the 50s most periods...and then
near 60 by the middle of next week.   Generally stayed close to
super blend temperatures.


.AVIATION /Discussion for the 28/18Z TAF Issuance/...
Issued at 100 PM EDT Wed Sep 28 2016

Mostly VFR with scattered showers through this evening. Then
areas of MVFR ceilings and visibilities or lower late tonight
and Thursday morning.

An area of low pressure over central Indiana will continue to
move southeast.  As a result there will be scattered showers
through the period.  An isolated thundershower possible through
00Z...but chances are too low to include mention in TAF`s at this
time.  Prevailing Ceilings will be at or above 7 thousand feet
through this evening then lowering to 1 to 2 thousand feet late
tonight with visibilities of 3 to 5 miles possible late tonight
in fog and or scattered showers.

Windds will become north 5 to 8 knots this afternoon and 5 knots
or less tonight.




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