377
FXUS63 KIND 061445
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
945 AM EST Thu Nov 6 2025

.KEY MESSAGES...

- Showers and isolated thunderstorms Friday, especially first half
  of the day

- Much colder starting Sunday with chances for light precipitation
  late Saturday-Monday...snow flurries most likely Sunday night

&&

.FORECAST UPDATE...
Issued at 944 AM EST Thu Nov 6 2025

Quiet and milder weather is expected today, though temperatures will
still be slightly above normal. Bumped max temps up just a bit per
morning obs trends running a bit quicker than forecast, which should
bring the area up into the upper 50s northeast to mid 60s southwest.

Mostly clear conditions are expected through the day with increasing
mid and high cloud late ahead of tomorrow`s system, which may bring
showers and perhaps a rumble of thunder to primarily northwest
portions of the area late tonight.

&&

.SHORT TERM (Today and tonight)...
Issued at 300 AM EST Thu Nov 6 2025

Moderate CAA behind yesterday frontal passage has led to
building high pressure and quickly diminishing winds. This
combination of clear skies and calm winds will lead to PBL
decoupling and a steep surface inversion of which could lead to
pockets of dense fog along river valleys. Expected lows in the low
to mid 30s this morning.

High pressure will remain throughout the day. A robust jet stream
remain aloft, contributing to the development of another shortwave
over the upper Mississippi Valley. As pressure trough deepens, winds
will veer back towards southerly, although the surface high will
still be influencing the overall conditions keeping skies mostly
clear outside of some upper cirrus this afternoon.

The progressive pattern will continue this evening into tonight as
the aforementioned shortwave nears from the west. Once again, a
developing nocturnal jet is expected, leading to breezier conditions
to develop shortly after sunset this evening. This edition of the
shortwave will have some moisture convergence along the developing
frontal boundary of which will lead to numerous showers to approach
from the NW late tonight.

Antecedent dry air should curtail precipitation onset some, but by
10Z, showers should be entering the CWA, and quickly progressing
eastward through central Indiana Friday morning (more on this in the
long term). Lapse rates are rather weak, but with a strong LLJ,
there could be enough lift for some areas of elevated instability
and therefor a few embedded thunderstorms cannot be ruled out
tonight.

&&

.LONG TERM (Friday through Wednesday)...
Issued at 313 AM EST Thu Nov 6 2025

Friday through Monday...

Increasingly active pattern surrounding this weekend`s staunch
transition to well below normal temperatures and the season`s first
consecutive hard freezes early next week...will begin with a weaker
wave producing scattered to briefly widespread rain showers Friday.
While a few strong storms are possible along and southeast of the
Ohio Valley as the wave strengthens...low confidence in anything
more than a brief downpour over central Indiana`s southeastern
zones.  Another breezy day will see gusts up to 20-30 mph veering
through southwest headings...bringing the last unseasonably mild day
for the foreseeable future, with highs around 65-70F.

Saturday`s generally fair conditions and still slightly-above normal
readings will be the calm before the cold blast...as various short
waves across the central CONUS work with a 510 dm H500 cut-off
trough that will plunge from south-central Canada on Sunday along an
axis over the Mississippi Valley.  Surface cyclogenesis ejecting
east just ahead of this synoptic shift...while likely tracking
across our northern counties Saturday night will bring rain showers,
especially north of I-70 late Saturday and Saturday night.

Mass of corresponding arctic surface high pressure plunging down the
High Plains will also push its eastern extent into central Indiana,
arriving early Sunday and likely mixing snow into any lingering
showers.  The upper trough`s core/axis will most likely swing east
across the region by the late weekend...favoring an only-snow
precipitation type to any flurries or few lake-enhanced snow showers
that may occur.  Any impacts would likely be limited to around the
Sunday night/early Monday timeframe when flurries would overlap with
temperatures falling below 25F...especially north and east of
Indianapolis which would have the best chance of catching the fetch
of lake-enhanced precipitation.

Heights/temperatures aloft will be the lowest around the Monday
morning timeframe...with the 1000-500mb 510 dm thickness nearing the
region`s northern counties, and H850 temperatures within the CWA as
low as negative 13 degrees Celsius.  Gradient flow should continue
through the early week as the broad, deep trough`s H500 height
minimum spins from Michigan to western Quebec.  Expect snow flurries
to wane around the Monday timeframe as decent vort wrapped around
the upper trough`s core spins east of southern Lake Michigan, with
occasional light snow most likely to linger north/east of the Indy
Metro.  Temperatures should fall below 25F for most locations for at
least two overnights, with probably only one daytime held under 40F.

Tuesday and Wednesday...

A return to a more zonal, albeit now slightly northwesterly, flow is
expected for the mid-week as the massive upper trough progresses off
the Atlantic coast/lifts into Canada.  The once huge/cold surface
ridge will set-up shop over the Deep South...and combine with a
Clipper-type disturbance crossing southern Ontario...to provide
robust southwesterly gusts.  Resultant moderation should be about 10
degrees/day, with at least 40s Tuesday and perhaps slightly above
normal/50s for the end of the period.  Partly cloudy yet rain-free
conditions will be the rule into the mid-week.

&&

.AVIATION (12Z TAF Issuance)...
Issued at 632 AM EST Thu Nov 6 2025

Impacts:

- Very patchy ground fog at KLAF and KBMG
- Gusty winds and showers tonight
- low MVFR to IFR ceilings tomorrow morning

Discussion:

Winds have quickly diminished overnight, with all sites either calm
or variable between 2-4kt. These calm winds with clear skies has led
to very isolated ground fog within river valleys, currently
impacting KLAF and KBMG. Winds will increase slightly today and
become consistent out of the south.

Overnight, a frontal boundary will near from the NW, creating gusty
winds out of the SSW and scattered showers. This will impact KLAF
first but will slowly push to the SE and impact all sites Friday
morning. Behind this boundary, overcast low MVFR to IFR skies with
isolated light showers are expected with winds shifting to the
W/WNW.

&&

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

&&

$$

UPDATE...Nield
SHORT TERM...Updike
LONG TERM...AGM
AVIATION...Updike