720
FXUS63 KIND 082007
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
307 PM EST Sat Nov 8 2025

.KEY MESSAGES...

- Rain arrives tonight.Thunderstorms possible from   Indianapolis
  southward.

- Isolated strong wind gusts possible with thunderstorms overnight.

- Turning colder with a chance of snow showers Sunday afternoon into
  Monday.

- Lows in the 20s Sunday night and Monday night, with wind chills
  in the teens at times Sunday night into Monday night

&&

.SHORT TERM (This evening through Monday night)...
Issued at 305 PM EST Sat Nov 8 2025

Strong ridge-building is ongoing across the western US, which in
turn is driving a trough southward over the central Plains. The
first signs of cyclogenesis are taking shape as the trough digs
southward this afternoon. Precipitation is beginning to break out
over Iowa and into northern Illinois, and this should consolidate
into a broad stratiform precip shield as the surface low develops.
By tonight, the low will be passing directly over central Indiana.

Thunderstorm Potential...

Most of the precipitation looks to initially be on the northern edge
of the low, mainly due to isentropic lifting. However, favorable jet
dynamics and positive vorticity advection further south will allow
for precipitation to rapidly develop near the low`s center. Enough
instability (50-250 J/Kg MUCAPE) looks present for scattered
convection after about 00z. Soundings show a shallow instability
layer, so robust deep convection does not appear likely. However,
dry low-level thermal profiles do support some marginal wind gust
potential despite the shallow convective nature.

Snowfall potential...

Guidance show strong cold air advection on the back side of the
departing low. Northwesterly winds between 15-25mph gusting to 30mph
appear likely, with temperatures quickly dropping into the 30s. Some
guidance is hinting at a quick change-over to snow before sunrise
Sunday as the low exits into Ohio. Even with a quick change-over,
the low is moving quick enough to limit snowfall through sunrise
Sunday. That does not mean we`re out of the woods for snow chances,
however.

Guidance is in good agreement showing our best snow chances not with
the low itself but with a secondary vort max dropping southward out
of Canada. This vort max will quickly follow Sunday morning`s
departing low with very cold air advection aloft. The cold air mass
will move directly over Lake Michigan, destabilizing it. The
combination of strong vorticity advection, an unstable air mass, as
well as a weak inverted surface trough, will allow for numerous
scattered snow showers Sunday evening and especially Monday morning.

Any snow through Sunday afternoon should have a difficult time
accumulating due to warm ground and marginal air temperatures.
Accumulations will be confined to grassy surfaces, should they
occur. Best chance of accumulating snow before noon Sunday looks to
be mainly northern Indiana, perhaps extending into our northern most
counties. That changes Sunday evening and into Monday morning,
however, as strong cold air advection allows temperatures to dip
into the 20s. This, combined with it being nighttime, should allow
snow to begin sticking to even paved surfaces. Accumulations under
an inch will be the most common, but a few pockets of 1-2 inches is
not out of the question. Snowfall totals should increase with
northerly extent due to lake enhancement. The best chance of locally
heavier snowfall is across our north and northeastern counties.

Temperatures...

As mentioned above, temperatures quickly fall into the 30s Sunday
afternoon with increasingly gusty winds. Highs on Sunday will likely
occur before sunrise for most. Temps are expected to continue
falling into the mid 20s by Monday morning. Combined with the wind,
wind chills into the low teens are likely. Highs on Monday may not
make it out of the low 30s with lows once again dropping into the
low to mid 20s Monday night.

&&

.LONG TERM (Monday night through Saturday)...
Issued at 305 PM EST Sat Nov 8 2025

Monday Night Through Thursday.

There may be a few lingering flurries/light snow showers across the
northern and northeastern portions of the forecast area, but as the
surface and near surface winds gain a more westerly vs northerly
component, expect to see the lake enhanced snow shift north out of
the forecast area. The air advecting into the area aloft will be
much drier which should allow for skies to clear through the night
with another night of lows in the low to mid 20s likely. As the
pressure gradients relax, wind speeds will decrease which will help
to keep wind chills slightly higher compared to Monday morning, but
will still fall into the teens.

Southerly flow will quickly return Tuesday with broad ridging across
all but the eastern portions of the US which will bring a return of
near to above normal temperatures by Wednesday. Deep mixing
Wednesday will help to drop dew points and bring RH values below 40
percent along with occasional wind gusts of 20 to 30 mph. Surface
flow will be more westerly on Thursday with lighter winds as another
upper level low moves across Southeastern Canada.

Friday and Saturday.

The ridge is expected to become more amplified Friday into the
weekend with a trough to the west of the Rockies and along the East
coast along with the low end threat for some light rain across the
Ohio Valley where a weak shortwave will move southeast along the
ridge. The warming trend is expected to continue into Saturday with
the potential for highs in the mid to upper 60s. Looking into the
next week, another low pressure system looks likely early in the
week which could bring widespread rain.

&&

.AVIATION (18Z TAF Issuance)...
Issued at 1238 PM EST Sat Nov 8 2025

Impacts:

- MVFR ceilings this afternoon at LAF
- Rain showers with MVFR/IFR conditions developing tonight
- Chance for thunderstorms at BMG
- Low ceilings with scattered rain / snow showers through Sunday
- NW wind gusts 20-25kt Sunday into Sunday night

Discussion:

VFR conditions are present at most terminals today except for LAF,
where MVFR ceilings have persisted through the day.

Increasing clouds are expected for the remainder of the afternoon as
a storm system approaches. Rain showers arrive after sunset with
conditions deteriorating to MVFR/IFR.

Some scattered thunderstorms are possible over southern portions of
Indiana, especially BMG. An isolated thunderstorm making it as far
north as IND is not out of the question.

MVFR/IFR conditions continue into Sunday with rain decreasing in
coverage and intensity. Scattered showers will persist into the
afternoon and evening, gradually mixing and changing to snow from
north to south.

Surface winds are expected to become gusty out of the northwest as
the system passes by. These winds will continue into Sunday night.


&&

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

$$

SHORT TERM...Eckhoff
LONG TERM...White
AVIATION...Eckhoff