textproduct: Indianapolis

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

- Precipitation chances increase beginning Sunday

DISCUSSION (This evening through Monday)

Issued at 253 PM EDT Mon Oct 5 2026

Strong surface high pressure remains in place across the region. The high's center is expected to pass to our north tonight, from west to east. This will cause winds to become more easterly tonight and eventually southeasterly on Tuesday. With an added southerly component to the wind field, warm air advection looks to commence. A gradual warming trend appears likely beginning tomorrow. High temperatures may climb into the 80s by Wednesday.

A broad trough skirts to our north later 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.

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 610 PM EDT Mon Oct 5 2026

Impacts:

- Patchy fog possible tonight at outlying terminals

Discussion:

Surface high pressure will drift east into the Mid Atlantic region through the forecast period with winds veering from easterly overnight...to south-southeast through the day Tuesday. Clear skies will prevail for much of the period with just a few thin cirrus possible by late Tuesday afternoon.

Patchy shallow ground fog is possible at the outlying sites late tonight and early Tuesday. Visibility may be briefly lower depending on wind speeds tonight and the TAFs will be refined in later updates as needed.

IND WATCHES/WARNINGS/ADVISORIES

None.