966
FXUS63 KIND 161027
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
627 AM EDT Thu Oct 16 2025

.KEY MESSAGES...

- Dry weather through Friday

- Active weather this weekend with rain expected late Saturday into
  Sunday along with occasional wind gusts of 30-40 mph.

- Turning cooler following frontal passage Sunday and Monday with
  additional rain chances Tuesday and Wednesday.

&&

.SHORT TERM (Today and tonight)...
Issued at 248 AM EDT Thu Oct 16 2025

Upper ridging over the central CONUS and surface high pressure
centered near the Great Lakes Region will promote quiet weather
conditions through the period. Current IR satellite imagery and
surface observations depict extensive low-mid clouds across central
Indiana. These clouds are associated with weak impulses moving along
the northern periphery of the ridge. The clouds are limiting diurnal
cooling so temperatures were increased by at least a few degrees in
most spots.

The upper ridge axis shifting towards the area and surface high
pressure becoming more established near Indiana should help to mix
out clouds after daybreak. Mostly clear skies are then expected
during the afternoon with highs reaching the upper 60s to mid 70s.
Light winds and clear skies this evening will allow for temperatures
to quickly. Look for temperatures to fall into the 40s across the
eastern half of central Indiana with generally upper 40s to low 50s
further west. Increasing high clouds are expected late overnight as
moisture streams in aloft from a shortwave moving through the
upper midwest.

&&

.LONG TERM (Friday through Wednesday)...
Issued at 248 AM EDT Thu Oct 16 2025

Friday Through Sunday.

The nose of an upper level ridge will be overhead Friday with
southerly surface and near surface flow gradually strengthening as a
low pressure system develops to the west. Details continue to
gradually become more clear with the GFS and its ensembles trending
more towards what the Euro has consistently shown with the polar low
being much more dominant than the low associated with the
subtropical jet. While the overall synoptic details are becoming
more certain, the mesoscale details such has orientation and axis of
the LLJ remains fairly uncertain which will strongly impact both the
magnitude of the axis of heaviest rain and its location.

Some of the higher resolution models such as the NAM are hinting
that the LLJ will have a more easterly orientation with a tighter
gradient while the GFS and Euro have a broader jet. Typically in
these patterns, the jet will be more narrow which favors the NAM
solution with its tighter associated QPF axis. This scenario would
create an area likely closer to the Ohio River where 1-3 inches will
fall with amounts of a half inch or less on either side of the axis.
With the rain expected to fall across an area that has seen at least
some appreciable rain over the last 10 days, there will be an
isolated flooding risk but even now the 6 hour FFG values are close
to the higher end expected QPF which would keep flooding more
isolated and nuisance.

With better agreement in the active weather primarily occurring
during the overnight hours, confidence continues to increase that
the heavy rain and isolated flooding will be the primary threat with
this system as the instability will generally remain elevated. There
is still 15-25kts of shear in the lowest 1km, but without better
surface based instability, the severe risk should remain southwest
of the forecast area.

Another concern with this system will be the strong gradient winds
both Saturday afternoon through Sunday afternoon with strong
southwesterly flow ahead of the system Saturday afternoon bringing
occasional wind gusts to around 30 mph followed by occasional wind
gusts of 30 to 40 mph Saturday night during periods of heavier
precipitation. There could be additional wind gusts as high as 40
mph Sunday afternoon with strong winds just above the surface and
models showing fairly favorable conditions for the mixing down of
winds.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 627 AM EDT Thu Oct 16 2025

Impacts: None

Discussion:

VFR conditions are expected through the period. Widespread clouds
are still present across much of central Indiana with ceilings
around 3500-5000ft. MVFR ceilings are unlikely, but cannot
completely rule out ceilings dropping to near 3,000 feet briefly.

Look for these clouds to begin mixing out later this morning as
surface high pressure becomes more established over the region.
Mostly clear skies are expected by the early afternoon. Light winds
around or less than 10kts are expected through the period with a
predominately east-southeasterly direction.

&&

.IND WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...Melo
LONG TERM...White
AVIATION...Melo