977
FXUS63 KIND 080804
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
304 AM EST Sat Nov 8 2025

.KEY MESSAGES...

- Dry today, Rain arrives tonight.

- 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 (Today and tonight)...
Issued at 302 AM EST Sat Nov 8 2025

Surface Analysis early this morning shows a broad trough in place
over the region, with cyclonic flow in place over Central Indiana. A
low pressure system was found over NB, pushing east. GOES19 shows
abundant mid and high cloud ahead of the low, pushing east across NB
and KS. Skies across Central Indiana were mostly clear as some
stratocu was found near the Great Lakes. Aloft, water vapor showed
NW flow across the CONUS and spilling from the Canadian Rockies to
Indiana. An upper low was noted over MT along with a a surge of
moisture ahead of this system producing the previously mentioned
clouds.

Today...

Dry weather will be expected today before larger changes arrive
tonight. Models show the upper low advancing eastward, allowing the
forcing dynamics and moisture to push east across Indiana through
the day. The surface low looks to reach MO by late this afternoon as
a warm front sets up over Indiana. Forecast soundings through day
reveal dry air within the lower levels, while saturation arrives
aloft, associated with the advancing cloud deck. Thus will trend
toward a dry forecast today, but expect increasing clouds through
the day. The clouds should limit full heating through the day and
highs should only reach the upper 50s to around 60.

Tonight...

The previously mentioned quick moving surface low is expected to
push across southern Indiana tonight. The 295K isentropic surface
shows moderate lift tonight, best focused across southern Indiana.
Specific humidities look to reach 3-4 g/kg as the forcing passes.
Forecast soundings suggest deep saturation passing overnight as the
low passes to the south. HRRR suggests the arrival of rain showers
this evening entering the Wabash valley before overspreading the
entire state. Showers appear to be more scattered initially as the
upper low approaches, but as it passes across Indiana, more wrap
around precipitation is expected. Thus there is high confidence for
rainfall tonight, especially overnight.

Of note, the upper pattern shows us the signal for the arrival of
the cold air for Sunday. By late tonight, strong ridging will have
developed over the western CONUS. This in combination with the
broader upper low over northern Ontario, will result in a stronger
trough digging through the Mississippi valley and setting up a cold
and enhanced northerly flow from Canada into the plains. This will
result in our much stronger surge of cold air arriving on Sunday.

&&

.LONG TERM (Sunday through Friday)...
Issued at 302 AM EST Sat Nov 8 2025

Sunday...

The long term will begin with a day of transition as broad and deep
upper trough over the eastern two-thirds of the CONUS...swings the
vort max at the southern tip of its inner core`s axis from Iowa into
central Indiana.  Surface low pressure deepening while departing
thru the eastern Great Lakes...will combine with 1040 mb elongated
surface ridge slowly building south/eastward into the region...to
promote brisk northwest surface flow gusting up to 20-30 mph.  Early
morning temperatures in the mid-30s to around 40F will struggle to
rise amid strong cold air advection, with readings dropping after
100P, and the freezing mark expected to reach northwest zones by
700P.

Lower confidence surrounds precipitation coverage and intensity as
the atmosphere rearranges from departing cyclone`s precip shield to
lake-effect/lake-enhanced flurries and potential snow showers
tracking from NNW to SSE.  A period of non-impactful wet snow is
possible early from the departing low should it deepen faster before
exiting the region, with temperatures too high to allow anything
more than reduced visibility.  Details within the vorticity of the
H500 level indicate ripples of better lift ahead of the arrival of
the trough`s core Sunday night...which may promote roughly 6-hour
periods of more/less active lake-effect convection reaching the
local region.  That said, overall north-central to eastern zones are
poised to see greater coverage of flurries with any stronger snow
showers likely only isolated through the day Sunday.  A dusting of
wet snow is possible on elevated/grassy surfaces through late
Sunday.

Sunday Night through Monday Night...

*Snow likely accumulating less than an inch for much of central IN

Sunday Night into much of Monday will bring the greatest coverage
and intensity of snow flurries/showers...as the ginormous trough`s
core likely plows south down Lake Michigan and then south-southeast
through Indiana.  This forcing along with H850 temperatures falling
below negative 10 degrees Celsius above the warm lake will produce
and advect snow showers/squalls into at least northern portions of
Indiana...with at least a period of widespread flurries and some
snow showers expected into the local CWA.  Despite a wide range in
solutions across various forecast guidance...it appears one to two
rounds of convective snow would be most likely within the pre-dawn
to afternoon hours Monday.  Spatially this would be most likely
north of the I-74 corridor, but the deep plunge of the upper forcing
to the Ohio Valley would certainly allow flurries to cross through
much of the region.

Embedded snow showers will likely produce at least brief moderate
snow that will accumulate on elevated and grassy surfaces, and also
untreated pavements from late evening Sunday into Monday morning.
A thin coating of snowfall on roads/sidewalks is certainly possible
in localized areas from these stronger convective SW`s...with any
location that encounters multiple snow showers seeing up to an inch
of total snowfall.  Accumulating snow is most likely along/north of
the I-74 corridor, although a thin coating is also possible for
points south Sunday night.  Greatest impacts will be late Sunday
night and Monday morning when liquid on pavements freezes to ice as
air temperatures below 25F freeze surfaces...with ice possibly
hidden under a thin coating of snow.

Tuesday through Friday...

Upstream short waves plunging slightly amid WNW flow into Middle
Mississippi Valley will maintain troughiness over eastern half of
the CONUS, albeit rather broad and much less amplified. A few
flurries, especially north of I-74 are a reasonable expectation for
Tuesday as a weak disturbance crosses the Midwest. Dry moderation
will otherwise be the rule courtesy of southwesterly gusts up to 20-
30 mph through Wednesday.

Tuesday morning to be the long term`s last below 30*F, with Tuesday
afternoon sporting the last sub-seasonal maximums of the week.
Pleasant and seasonal conditions for mid-November through Wednesday-
Thursday under mostly clear skies.  Moderate southerly flow by the
end of the workweek will return above normal, mild readings possibly
surpassing 60*F over some of the region. The normal max/min at
Indianapolis through the long term will fall from 55/37 to 52/35.

&&

.AVIATION (06Z TAF Issuance)...
Issued at 1240 AM EST Sat Nov 8 2025

Impacts:

- Brief MVFR VIS possible within 11Z-14Z at TAF sites except KIND
- Winds 7KT/less becoming variable Saturday evening from surface low
- Ceilings quickly falling at end of TAF period at KLAF/KIND

Discussion:

VFR conditions will mainly prevail through at least most of the TAF
period over central Indiana sites.  Generally fair conditions
overnight into Saturday afternoon as subtle high surface high
pressure builds into region between waves riding quickly amid zonal
upper pattern.  MVFR visibility is possible in BR during 11Z-14Z
this morning, especially at KBMG...with no VIS reduction expected at
KIND.
Light winds through Saturday morning will be from westerly headings
if not variable.

High clouds will increase from NW to SE ahead of evening -SHRA.
Ceilings to fall to low-VFR at KLAF/KHUF by the end of the period...
and at KIND, possibly quickly to IFR levels, pre-dawn Sunday.
Developing surface low pressure to track eastward into region, to
near KIND by 06Z Sunday...with surface winds therefore becoming
variable/backing Saturday night, and increasing above 7KT by 06Z at
most sites.


&&

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

$$

SHORT TERM...Puma
LONG TERM...AGM
AVIATION...AGM