767
FXUS63 KIND 280150
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
950 PM EDT Sun Sep 27 2026

.KEY MESSAGES...

- Mostly sunny early this week with warming temperatures.

- Patchy fog possible Monday and Tuesday mornings.

- Dry conditions persist through Wednesday, with the next chance for
  rain arriving Thursday and then continuing into the weekend.

&&

.FORECAST UPDATE...
Issued at 949 PM EDT Sun Sep 27 2026

The forecast remains in great shape with only minor adjustments
needed. Look for quiet weather conditions through the overnight as
surface high pressure remains in control across the region. Mostly
clear skies combined with very light winds will support patchy fog
development again by late tonight. Very limited cloud cover and
light winds is supporting a rapid drop in temperatures this
evening. Latest observations depict temperatures are in the 50s
across much of central Indiana. Expect continued cooling through
the overnight with lows mostly in the mid-upper 40s.

&&

.DISCUSSION (This evening through Sunday)...
Issued at 215 PM EDT Sun Sep 27 2026

Rest of This Afternoon through Tuesday...

Subsidence on the west side of the upper low on the east coast of
the USA along with surface high pressure will continue to provide
dry and quiet weather for central Indiana.

Mainly some passing high clouds are expected, especially across the
western forecast area. Good radiational cooling will occur tonight
and Monday night, so have cut blended guidance`s temperatures both
nights. These conditions will allow for patchy fog once again late
tonight/early Monday and late Monday night/early Tuesday.

With the dry atmosphere in place and plentiful sunshine expected,
raised Monday`s and Tuesday`s highs from blended guidance.

Wednesday through Next Weekend...

A northern stream upper trough will move through Canada and the
Great Lakes into Friday, and this will bring a surface front into
the area by Friday.

Meanwhile, an upper low across the southwestern USA will gradually
move northeast. This low will have taken in tropical remnants and
will thus have good moisture with it. A surface low pressure system
will accompany the upper system.

The upper low will weaken as it moves north and east, but guidance
continues to differ on its speed and what happens with it. Some
guidance has the northern stream absorb the remnants of the upper
low while others keep the upper low separate and farther southwest.
This also affects the eventual location of the associated surface
low pressure system. Thus, there is higher uncertainty in the
forecast for later this week.

It now appears forcing will arrive later than previously thought, so
Wednesday looks dry during the day. Otherwise, rain chances will be
around Thursday into next weekend. With the uncertainty, confidence
in timing and location of the highest PoPs remains low. With the
weakening upper low still having tropical moisture, locally heavy
rain will be a threat late week.

With the slower arrival of the system, well above normal
temperatures (upper 80s not out of the question for parts of the
area) will continue into Thursday. Afterward, clouds/rain/cooler air
behind a front will lead to below normal temperatures next weekend.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 712 PM EDT Sun Sep 27 2026

Impacts:

- Patchy fog possible overnight into Monday morning

Discussion:

Outside of patchy fog overnight into Monday morning, VFR conditions
are expected. Some guidance hints at broken stratus forming near
KLAF late tonight, but not confident enough to include. Will have
to watch though as some stratus formed this morning well northeast
of the area.

Patchy ground fog will likely develop overnight at all but KIND
(where the urban heat island will protect the site). Will continue
to use a TEMPO for MVFR fog at all but KIND. Brief IFR conditions
cannot be ruled out.


&&

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

$$

UPDATE...Melo
AVIATION...Melo
DISCUSSION...50