textproduct: Indianapolis

KEY MESSAGES

- Heat Advisory in effect for all of central Indiana through Thursday evening with peak heat index values up to 105 are possible each afternoon

- Isolated to scattered thunderstorms will be possible at times late this week through the weekend.

DISCUSSION (Today through Tuesday)

Issued at 327 AM EDT Wed Sep 2 2026

Deep ridging over the central CONUS will be the predominant driver of our upcoming weather over the next several days. Warm SW flow has pushed temperatures well above normal, with high temperatures in the low to mid 90s through at least Thursday. This in combination with dew points in the low 70s will push heat index values above 100 each afternoon, prompting a Heat Advisories until 8PM Thursday.

The ridging is then expected to retrograde which could introduce showers and storms into portions of the area as early as late in the day Thursday. However, there is a bit of uncertainty with this as it is unclear on how quickly the ridge will drift back west and it's amplitude. Confidence in convection on the northern periphery of the ridge is high, but how far south this area of convection reaches is where confidence wanes. Currently the expectation is for a majority of any precipitation Thursday afternoon to remain just north of the area, but the margin for error is small. Should these storms make it into central Indiana, there is a threat of severe weather with them with damaging winds the main threat.

A strengthening trough over the east coast will help to push the ridge further west late week into the weekend. This could lead to additional chances for showers and storms but again low confidence on timing and location.

Temperatures will be slightly lower going into the weekend but still expected to be above normal. The start of the new week could see nearer to normal temps but well above normal can't be ruled out for the extended period with a few chances for PoPs.

AVIATION (06Z TAF Issuance)

Issued at 211 AM EDT Wed Sep 2 2026

Impacts:

- Wind gusts to 16KT Wednesday afternoon

Discussion:

VFR conditions to continue through the period under a stacked, hot subtropical ridge whose center will slowly drift from the TN Valley into the Southern Appalachians.

Can't rule out patchy fog at the outlying sites tonight given mostly clear skies and lighter winds at those sites overnight. Confidence not high enough to include in TAFs.

Clouds through the period will include occasional cirrus flowing around the ridge's northern tier, and therefore most likely at KLAF/ KIND and afternoon cumulus that may occasionally reach SCT coverage. Southwest winds expected through the period with an increase in speed during the day Wednesday with gusts near 16kt possible at LAF during the afternoon.

IND WATCHES/WARNINGS/ADVISORIES

Heat Advisory until 8 PM EDT Thursday for INZ021-028>031-035>049- 051>057-060>065-067>072.