169
FXUS63 KIND 120455
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
1155 PM EST Wed Nov 11 2026

.KEY MESSAGES...

- Patchy light rain will continue at times tonight, mainly in the
  northern forecast area

- Scattered to numerous showers with much colder air late week. A
  few snowflakes possible as well Friday morning

- Dry weather returns this weekend into next week with a slow
  warming trend

&&

.FORECAST UPDATE...
Issued at 943 PM EST Wed Nov 11 2026

Low pressure was exiting central Indiana to the east this evening,
taking the convection with it. Cooler air is moving in behind the
low, but another push of cooler and drier air was moving into the
northwest forecast area. Additional showers were moving into the
northern forecast area associated with some upper energy.

Adjusted PoPs to reflect the above. The showers associated with the
upper energy will move east southeast across the northern forecast
area into the early overnight. Went with chance or lower category
PoPs for these. Some lake enhanced showers may move into the far
north overnight, so continued low PoPs for these.

There may be some breaks in the cloud cover at times, so continued
with a partly to mostly cloudy forecast. Tweaked hourly temperatures
based on latest trends, but forecast low temperatures look
reasonable so made no changes there.

&&

.DISCUSSION (This evening through Wednesday)...
Issued at 221 PM EST Wed Nov 11 2026

A positively tilted shortwave will aid in the development of a
surface low, of which will pass through central Indiana later today
through tonight. Satellite imagery shows a well defined warm frontal
boundary with modest elevated instability just to the north. There
is a faintly defined cold front developing along/near the
Mississippi, but it is in the very early stages of FGEN with mainly
low level convergence as the primary driver. As the day progresses,
diurnal/differential heating along with low level pressure depletion
will aid in some additional FGEN, but without strong temperature
advection, the overall low pressure system will likely remain
relatively immature until after is pushes east of central Indiana.

Without strong temperature advection, the primary driver for today`s
convective threat will likely default to modest vorticity advection
and low level pressure depletion just ahead of the shortwave.
Current observations showcase an amplified and concentrated area of
CVA across IA/IL, but RAP analysis is indicating that this will
become for diffuse as the day progresses, with a more broadly
defined area of CVA this afternoon and evening. Pressure depletion
is likely to follow closely to the already defined warm front of
which is currently over northern portions of central Indiana. This
is where we expected the greatest concentration of convection to
occur, with mores scattered to isolated cells developing south of
this area over the rest of central Indiana.

Regarding the severe threat today, the primary concern is for
consistent small hail and isolated damaging wind gusts. While
tornadoes cannot be completely ruled out, the lack of low level
directional shear along with a fairly dry and well mixed PBL will
inhibit tornadogenisis considerably. If a tornado were to occur, it
will likely be near or along the frontal boundary where locally
enhanced backing is observer, or where cell mergers occur within a
more organized convective cluster.

The main focus for damaging winds is expected to be along the I-74
corridor where greater mid level dynamics will likely aid in
convective organization, tapping into a very dry mid level layer.
Outside of this area, very isolated damaging winds cannot be ruled
out, but should mostly be contained to 35-45MPH winds within sparse
convective cells. Small hail is likely to be fairly prolific within
strong cells today due to the HGZ well within the area of steep
lapse rates (7.2-7.7C/km). Weak shear within this layer along with a
shallow corridor of CAPE is likely to keep most hail stones below
1". That said, there is a low end threat for these smaller hail
stones to congeal together to create large hail clusters. We will
watch for this within strong convective updrafts where numerous
cells are merging.

After the low passes to the east overnight, strong NW flow is
expected to develop as the PBL maintains instability beneath modest
CAA. Gusts are expected to peak around 30-35MPH, with consistent
gusts around 25MPH. This NW flow will push much cooler air into the
region with the coldest air of the Fall arriving for Thursday and
Friday. This cold air will be further reinforced by an amplifying
upper trough with a close low developing over the eastern Great
Lakes by Friday night. Multiple waves will pivot around the flank of
the upper level trough maintaining plenty of low level clouds and
periodic precipitation through the period.

The strongest of the short waves will track across the region on
Thursday. As it does so the wave will interact with strong cold
advection and steepening mid level lapse rates to generate scattered
to numerous light rain showers peaking in coverage during the
afternoon and focused particularly across the northeast half of the
forecast area. The addition of brisk northwest winds and broad
stratus will make for a raw chilly day across the area with highs
remaining in the 40s.

A strong upper level trough will continue to remain in place during
the day Friday. Despite limited moisture with dew points in the
upper 20`s to low 30`s, 15-25 kts of cold NNW flow off of Lake
Michigan supports the development of a north-to-south oriented band
of precipitation extending down towards the I-70 corridor. Even with
temperatures in the mid 30`s to low 40`s at the surface, freezing
temperatures just above the surface support the potential of a few
embedded snow showers and/or graupel.

The upper level trough is expected to shift east starting Saturday
bringing with it the transition to a ridging pattern that is
expected to persist through the end of next week. Other than some
scattered lingering cloud cover Saturday and Sunday, next week will
bring the return of more quiet seasonable weather and mainly sunny
skies. High temperatures next week will range in the 40`s through
upper 50`s with lows in the low to mid 30`s.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1155 PM EST Wed Nov 11 2026

Impacts:

- A few light showers tonight, especially at KIND

- Scattered to numerous showers developing at all terminals on
  Thursday

- Gusty winds diminish late tonight then return mid morning Thursday

- MVFR ceilings expected at KLAF/KIND for much of the day Thursday
  and at all terminals Thursday night

Discussion:

The cold front is now east of the region late this evening and gusty
N/NW winds have developed in its wake. A few showers will drift
across the northeast half of central Indiana through daybreak
Thursday with periodic MVFR ceilings. Wind gusts will drop off in
the predawn hours.

A much stronger wave aloft will drop south from the Great Lakes on
Thursday with showers increasing in coverage by the afternoon and
evening across the entire area. MVFR stratocu will persist at KIND
and KLAF for much of the day Thursday then spread to KBMG and KHUF
by Thursday evening. Northwest wind gusts up to 25kts will resume by
mid morning and continue for the rest of the day before decreasing
Thursday night.

&&

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

&&

$$

UPDATE...50
AVIATION...Ryan
DISCUSSION...Ryan/Updike/SM