616
FXUS63 KIND 172009
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
309 PM EST Mon Nov 17 2025

.KEY MESSAGES...

- Rain overspreading Central Indiana late tonight through tomorrow

- Thunderstorms tomorrow across South Central Indiana, a few may be
strong with hail as a primary threat

- Seasonable temperatures through next weekend with another round of
rain expected Thursday into Friday

&&

.SHORT TERM (This evening through Tuesday)...
Issued at 309 PM EST Mon Nov 17 2025

Dry weather continues for the rest of the day today before rain
overspreads Central Indiana from the west later tonight. Satellite
imagery shows high clouds beginning to spread eastward over the
state, while the main area of low pressure to watch is still over
Colorado/Kansas. Expect clouds to increase through the evening hours
as the system nears while winds become easterly and temperatures
remain fairly steady in the low to mid 40s.

Guidance today has slowed down the arrival of rainfall by a few
hours. This aligns with current thoughts as local soundings show
very dry antecedent conditions, making it difficult for rainfall to
reach the ground initially. The best forcing for ascent and moisture
advection into the area will be around and after 08z as a 35-50 kt
southwesterly low level jet spreads into the state. The better
dynamics will be closer to the track of the low as it traverses
Southern Indiana and the Ohio River on Tuesday, so expect there to
be a rainfall gradient across the state with areas north of I-70
getting closer to 0.25-0.5" of rain while south of I-70 may pick up
0.5-0.75+ inches. As far as timing/duration, expect steadier and
more widespread rainfall to persist into the mid morning hours
before shifting south and east early afternoon. Rainfall likely
continues later into the day for South Central Indiana as the low
tracks through the region, sparking off additional showers and
storms along and south of the warm front.

Keeping the thunderstorm threat in South Central Indiana south of
the west to east oriented warm front. North of this boundary,
temperatures in the 40s and a more stable atmosphere should limit
thunderstorm potential; while a much warmer and unstable environment
aloft exist south of the boundary supportive of thunderstorm
development. Thunder chances increase after sunrise across the south
and continue through the afternoon. Watching for the potential of
additional, more discrete storms to develop during the late morning
and afternoon hours after the main round of rain pushes east. There
has been consistency in CAMs soundings showing sufficient MUCAPE
above a low level inversion and bulk shear supportive of a few
strong elevated storms capable of producing small hail. While
widespread severe weather is not expected, would not be surprised to
see a few strong storms from Sullivan County to Decatur County and
points south. Will monitor this threat over the next 12-18 hours and
update the forecast accordingly.

&&

.LONG TERM (Tuesday night through Monday)...
Issued at 309 PM EST Mon Nov 17 2025

The extended portion of the forecast starts out Tuesday night with
one in a series of shortwave troughs moving through the Ohio Valley
region. The greatest instability will have pushed south of the
forecast area by early Tuesday evening, but an isolated TS can not
be ruled out given around 500 j/kg of mucape through about 03Z
before shortwave ridging/subsidence set in.

In the wake of this shortwave, a subsidence inversion centered
around 700 mb will remain in place through Thursday. Subtle, weak
waa in the 850-700 mb layer beneath this inversion will lead to
overcast skies and likely some drizzle/patchy light rain during the
peak waa period from Wednesday night into Thursday. Another in a
series of shortwaves will then move out of the Southwest into the
Southern Plains Thursday and into the Ohio Valley on Friday. Likely
to categorical pops across the forecast area will begin Thursday
night in the baroclinic leaf/intensifying waa zone, with the bulk of
the heaviest precipitation occurring Friday associated with the main
shortwave trough passage. Storm total QPF amounts from 1-2 inches
look possible for southern portions of the forecast area given the
extended zone of focused waa/vertical motion fields. Lesser QPF
amounts generally under 1 inch are expected in northern portions of
the forecast area. Thunderstorm/marginal severe storm chances look
to be very limited given the expected location of the surface-850 mb
warm front/track of the surface low generally across Ohio River.
However, since this is still 4 days out later forecasts may see a
slight chance of TS added depending on any future track adjustments.

The weather dries out for the weekend owing to surface high pressure
building southward from the upper MS valley and mid level shortwave
ridging moving eastward out of plains into the Ohio Valley. There is
a slight chance of precip increasing again early next week
associated with yet another shortwave trough moving out of the
southern plains. The well advertised cold wave event still looks to
be at least several days out beyond the extended and the
timing/intensity is very uncertain given the potential very strong
jetstream developing over the East Pac/Intermountain west around
Thanksgiving.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 1236 PM EST Mon Nov 17 2025

Impacts:

- Rain moving in after 06Z tonight, little to no vsby restrictions
- Sct thunderstorms possible at KBMG after 15z tomorrow

Discussion:

VFR conditions are expected through at least 06z tonight at all
sites as high pressure slowly shifts eastward today. Light to calm
winds this afternoon become easterly around and under 5 kts this
evening through late tonight. As the low pressure area near through
South Central Indiana late morning Tuesday, expect winds to become
southeasterly (120-150 deg) around 8-12 kts.

Low level dry air should keep cigs at VFR levels through the night
despite rain arrive after 06z. Cigs slowly lower during the early
morning hours and may briefly become MVFR under a heavier shower or
thunderstorm. There are some indications that cigs lower to MVFR
levels toward the end of the current TAF period and into Tuesday
evening, will monitor this and add it to later forecast issuances as
confidence increases.

The thunderstorm threat should be confined to South Central Indiana
and points southward, with KBMG on the northern edge of the threat.
Best chance for a thunderstorm will be after 14z and into the
afternoon hours. Vis and cigs may briefly drop to MVFR to IFR levels
during heaviest showers or storms.


&&

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

$$

SHORT TERM...CM
LONG TERM...Crosbie
AVIATION...CM