773
FXUS63 KIND 262347
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
747 PM EDT Mon Oct 26 2026

.KEY MESSAGES...

- Dry and unseasonably high temperatures to continue through Friday,
  afternoon highs in the 70s

- Patchy dense fog possible south of the I-70 corridor tonight
  into the morning. Uncertainty is high on fog coverage.

- A wetter pattern may take shape for the Halloween weekend and/or
  the following week

&&

.DISCUSSION (This evening through Monday)...
Issued at 151 PM EDT Mon Oct 26 2026

The broader synoptic pattern will remain fairly stagnant over the
next several days, but weak progression of the longwave pattern,
along with downstream impacts of low passages over the
Northern/Canadian Plains will still create slight fluctuations to
surface conditions throughout the week.

The main impact over the next 48 hours is likely going to be fog
development late tonight into tomorrow morning. Deep ridging aloft
is becoming cutoff from the upper level flow, leading to a broad
area of high pressure aloft. This has lead to modest subsidence and
building pressure near the surface of which is sinking southward
ahead of a weak frontal passage ahead of upstream lows. This will
eventually shift winds to the east, but in the meantime winds will
start to calm around dusk. Areas along and south of I-70 will have
the most prolonged period of calm winds leading to a greater
likelihood of fog development. Given scattered upper level clouds
and very dry surface conditions, there is some uncertainty in the
coverage of fog, but at a minimum river valleys and well irrigated
fields will likely see 1/2mi or less visibilities.

The other forecast impact for this week will be increasing winds
Wednesday through Friday. By Wednesday, the mid to upper trough will
near from the west leading to more unified SW flow, an increase in
the pressure gradient and greater diurnal mixing. All of these
combined will likely lead to gusty conditions each afternoon with
sustained winds around 8-12kt with gusts around 20kt. This greater
SW flow will also provide a slight warming trend with afternoon
highs approaching 80 later this week.

Any lingering upper ridging will exit as multiple upper troughs move
through next weekend. Uncertainty remains high on the details, but
for now it appears that the best forcing and moisture will arrive
overnight Saturday night into Sunday morning, with only low chances
for rain during Halloween evening events.

If the front remains north, highs will be in the 70s. However, a
more southern front as well as any rain would keep readings lower,
especially on Sunday.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 746 PM EDT Mon Oct 26 2026

Impacts:

- IFR/worse visibility possible after 09Z at KHUF and KBMG

Discussion:

Surface high pressure will keep winds light and variable overnight
for most of central Indiana. Since the high center is not directly
overhead, mid/high level cloud cover from a system out west has
been present for much of the day. These clouds should diminish
overnight before increasing again Tuesday afternoon.

A weak cold front from the north will advance into central Indiana
tonight. The front may not reach much farther than LAF, where we
will include a brief period of northerly winds overnight. Winds then
become southeasterly by morning. By Tuesday afternoon, winds are
expected to take on a southwesterly direction.

Fog is likely tonight, especially at HUF and BMG. LAF has a chance
as well but lower probability due to the cold front arriving during
the night. Fog may reduce visibility to IFR or worse at times.

&&

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

$$

AVIATION...Eckhoff
DISCUSSION...Updike