749
FXUS63 KIND 062156
AFDIND

Area Forecast Discussion
National Weather Service Indianapolis IN
556 PM EDT Tue Oct 6 2026

.KEY MESSAGES...

- Dry through Saturday with most days at near to above normal
  temperatures under the influence of high pressure

- Fire weather conditions will require monitoring as several
  afternoons will likely feature minimum RH values well down into
  the 30s if not lower at times

- Rain chances return beginning early Sunday

&&

.DISCUSSION (This evening through Tuesday)...
Issued at 248 PM EDT Tue Oct 6 2026

Surface high pressure has slid to our east allowing winds to become
southeasterly. With an added southerly component to the wind field,
warm air advection has commenced. A gradual warming trend will
continue through tomorrow. High temperatures may climb into the 80s
on Wednesday.

A broad trough skirts to our north late Wednesday into Thursday with
an associated surface low over the Hudson Bay. Though displaced well
to our north, this low will drag a surface cold front through the
Ohio River Valley. Cold air advection takes hold on Thursday with a
cool-down anticipated. Highs dip back into the low 70s both Thursday
and Friday; lows once again into the 40s. Patchy fog is possible
during the overnights with efficient radiational cooling.

The pattern repeats with surface high pressure arriving and then
passing to our northeast on Friday. Winds regain a southeasterly
component allowing gradual warming to begin again. Highs climbing
into the upper 70s to near 80 are possible this weekend. Clear skies
aside from occasional cirrus are expected through Saturday.

Dry conditions combined with daytime relative humidity values near
30 percent may allow for increased fire weather potential through
Saturday. Surface wind speeds are likely to remain light, thus
mitigating the threat.

SUNDAY ONWARD

Warming will continue into Sunday depending on whether a disturbance
over the Gulf lifts north or northeastward. Guidance is beginning to
hone in on the idea of tropical development over the southwestern
Gulf and taking the resulting system northward in conjunction with a
cut off upper-level low over Texas. This is a highly uncertain
situation, since multiple factors are in play that have yet to
develop.

First, the tropical cyclone may not develop at all and simply remain
a tropical wave / moisture plume. Second, the upper-level low over
Texas fails to materialize or is too fast/slow. Any combination of
these may dramatically affect the outcome for Indiana. Recent model
trends have been towards the idea of tropical development with an
eventual merger between the upper low and tropical cyclone/remnants.

We can boil it down into two scenarios, however. One where it rains
and one where it does not. Should moisture lift northward into
Indiana, whether associated with a weak or strong low, then
temperatures are likely to be suppressed and rainfall chances high.
Should the system fail to develop or miss entirely, then above-
average warmth continues into the new week. These systems are within
a larger-scale ridge, so avoiding any precipitation will lead to a
continued warming trend.

&&

.AVIATION (00Z TAF Issuance)...
Issued at 556 PM EDT Tue Oct 6 2026

Impacts:

- Shallow ground fog possible again late tonight, otherwise VFR.
- Periodic gusts near 20kts possible Wednesday afternoon

Discussion:

Strong high pressure over the Great Lakes and Ontario will continue
to dominate weather across the region through tonight. The high will
shift to the eastern Great Lakes on Wednesday with a weak frontal
boundary dropping through the area. With deep subsidence lingering
across the area...only a subtle increase in cirrus will signal the
frontal passage along with a shift in winds to westerly. Periodic
gusts to near 20kts is possible Wednesday afternoon.

Some patchy ground fog cannot be ruled out predawn Wednesday but
little impact is expected from this should it occur.

&&

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

&&

$$

AVIATION...Ryan
DISCUSSION...Eckhoff