textproduct: Indianapolis

KEY MESSAGES

- Scattered to numerous showers and with some storms early this morning, with showers diminishing during the day

- Locally heavy rain is possible early this morning

- Much cooler temperatures for the first half of the week, gradually warming back to near normal levels by next weekend

DISCUSSION (Today through Sunday)

Issued at 258 AM EDT Mon Sep 21 2026

Early This Morning...

The surface front has moved south of central Indiana, but a couple of upper impulses along with a surface wave riding along the front are bringing enough forcing for numerous showers and some thunderstorms to move into the area.

This forcing will continue through the predawn hours, so have gone with higher PoPs over much of the area. For much of the area, CAPE is elevated with an inversion closer to the surface. Will have to watch the far south where better instability remains closer to the surface, but odds for any severe weather remain low. Heavy rain and localized flooding will be the threats as some training of cells may occur.

Today and Tonight...

At 12Z, rain from one of the upper impulses will likely still be ongoing for parts of the area. Will go likely PoPs for portions of the east and southeast early in the period. Some of the latest hourly guidance is showing another upper impulse generating more numerous showers moving west to east during the morning. Not confident enough yet to up PoPs elsewhere at this time, but will keep an eye on how things develop.

Otherwise, chances for rain will diminish during the day as overall forcing exits. Will have most areas dry by 21Z.

Moisture will be trapped below an inversion so will keep skies mostly cloudy. With the clouds and cooler air behind the front, highs will only reach the middle 60s far northeast to near 80 far southwest.

Clouds will continue to hang around tonight. Lows will be in the 50s.

Tuesday and Wednesday...

A weakening upper low will approach the area on Tuesday. Forcing will be weak, so for now have not gone with any mentionable PoPs. However, wouldn't be surprised to see some isolated showers develop during the afternoon.

The upper low will be east of the area on Wednesday. Most forcing will be east of the area, but an isolated shower is possible in the extreme east during the afternoon.

Lingering moisture will keep skies mostly cloudy on Tuesday, with western areas seeing some partial clearing on Wednesday. Highs will generally be in the upper 60s to middle 70s.

Thursday and beyond...

Surface high pressure will keep the weather quiet during this period. Temperatures will remain below normal into the first part of the weekend, then readings may return to above normal (highs around 80) by next Monday.

AVIATION (06Z TAF Issuance)

Issued at 115 AM EDT Mon Sep 21 2026

Impacts:

- Numerous showers at most sites before 12Z. Thunder is possible, mainly at KHUF - Predominant MVFR ceilings expected through the period. IFR at times before 12Z - Gusts near 20kt possible, mainly at KLAF

Discussion:

A couple of upper waves will bring numerous showers and scattered thunderstorms across all but KLAF, where showers will be fewer and weaker.

Ceilings will be predominantly MVFR through the period. MVFR visibility is possible in the rain, and ceilings will bounce into IFR at times with the rain at KLAF/KIND. IFR cannot be ruled out elsewhere, but for now confidence is not high enough to include.

Rain will diminish after 12Z, but the MVFR ceilings will continue.

IND WATCHES/WARNINGS/ADVISORIES

None.