textproduct: Indianapolis

KEY MESSAGES

- Clouds diminishing through this evening with patchy fog late tonight in eastern parts of central Indiana

- Near record highs Monday and Tuesday

- Periodic showers and thunderstorms for midweek

- Coolest air of the season so far next weekend with growing confidence in a widespread frost Saturday night

DISCUSSION (This Evening through Sunday)

Issued at 221 PM EDT Sun Oct 11 2026

The remnants of Hurricane Isaias will move away to the east with upper level ridging set to build in immediately for the early part of the week. This will set the stage for near record breaking warmth Monday and Tuesday. A frontal boundary will move into the area for midweek with periodic rain and storms Tuesday night through Thursday. The coolest air of the season so far will follow for next weekend.

Rest of This Afternoon through Tuesday

The back edge of the stratus deck continues to make slow but steady eastward progress across central Indiana early this afternoon. Skies were mostly sunny in the Wabash Valley with thicker clouds largely confined to areas east of Interstate 69. Temperatures varied widely as a result of the clouds...ranging from the lower 60 in eastern counties to the mid 70s in the lower Wabash Valley.

The departure of the stratus associated with what is left of Isaias will be followed by high pressure and mainly clear skies tonight. With winds becoming near calm...potential exists for patchy fog formation in the predawn hours through daybreak Monday focused primarily over the eastern half of the forecast area. The fog will burn off quickly Monday morning as boundary layer mixing commences.

The arrival and expansion of a broad upper level ridge into the Ohio Valley on Monday will signal an abrupt transition...and the first of several upcoming over the next seven days...as stronger southwest flow develops between a frontal boundary over the upper Midwest and the aforementioned high pressure as it settles along the Gulf coast. Strong warm advection will commence and result in well above normal temperatures for Monday and Tuesday across the region. Highs may flirt with 90 degrees in the Wabash Valley both days. For KIND... record highs of 86 for both Monday and Tuesday will be threatened. The frontal boundary over the Great Lakes will drift south towards the area late Tuesday but any convection is expected to remain to the north through Tuesday evening.

Tuesday Night Through Sunday

An increasingly amplified flow aloft driven first by an upper low over the Rockies and then more significantly by a deepening northern stream trough will flatten the ridge over the Gulf coast while initiating a substantial pattern change for the region late week into next weekend. The aforementioned boundary will remain in a quasi-stationary state over the Ohio Valley midweek before lifting back north Thursday in response to a surface low ejecting out of the Rockies and increased upper jet phasing. Rain with embedded thunderstorms will increase in coverage across the region as a result Wednesday and Thursday as multiple surface waves ride along the boundary. There remains at least some potential for a few stronger storms...especially ahead of a strong cold front Thursday afternoon but the potential for an abundance of clouds and rainfall poses some uncertainty in this prospect. With a deep moisture plume pooling along the front aided in part from remnant moisture from the two eastern Pacific hurricanes...there is the possibility for some locations to see one to two inches by Thursday night.

The cold front will sweep across the region Thursday night and early Friday. In the wake of the frontal passage...the aforementioned upper trough will settle and amplify across much of the eastern half of the country. A much cooler airmass will overspread the region with strong cold advection in place. Highs primarily in the 60s on Friday will remain in the 50s Saturday making for the coolest daytime temperatures experienced in over 5 months. While a lack of boundary layer decoupling may limit frost accrual to sheltered locales Friday night...confidence continues to grow in a widespread frost for much of the area on Saturday night as lows fall into the 30s. Subfreezing temperatures are squarely on the table for some of our normal cool spots as well Saturday night.

AVIATION (18Z TAF Issuance)

Issued at 1207 PM EDT Sun Oct 11 2026

Impacts:

- Lower stratus diminishing from the west this afternoon - Patchy fog at KIND early Monday morning

Discussion:

Stratus deck continues to steadily erode from the west early this afternoon with the expectation that it will be east of all the terminals within a few hours. Some cu development will develop on the backside of the stratus deck but the overall trend will be towards clear skies by late afternoon and early evening. N/NW wind this afternoon will become light and variable this evening.

Patchy fog is expected to develop across eastern Indiana in the predawn hours Monday and may spread back towards KIND for a few hours near daybreak. Otherwise VFR conditions are expected for the rest of the forecast period with southwest winds around 10kts developing Monday.

IND WATCHES/WARNINGS/ADVISORIES

None.