textproduct: Indianapolis

KEY MESSAGES

- Quiet weather with near normal temperatures through Friday

- Showers and thunderstorms return this weekend, heavy rain possible

- Warming trend possible for the first week of August

FORECAST UPDATE

Issued at 936 PM EDT Tue Jul 28 2026

Forecast is in good shape this evening. While actual cloud cover has diminished, elevated smoke continues across the area. With the elevated smoke continuing through the night, upped sky cover some to account for this.

Slowed down arrival of drier air south based on latest observational trends. In the north, where drier air is arriving, temperatures have cooled quickly. Adjusted temperatures there as needed.

Tweaked low temperatures down in favored cold areas. Otherwise, the forecast low temperatures look good given expected conditions.

Can't rule out some ground fog near sunrise, but with drier air moving in and some winds lingering, feel odds are too low to mention.

DISCUSSION (This evening through Tuesday)

Issued at 252 PM EDT Tue Jul 28 2026

Low pressure over eastern Canada, which was the cause of yesterday's storms, continues to move away from the Great Lakes region. Surface high pressure is now building in from the northwest, with a cooler and drier air mass filtering into Indiana. Dew points have slowly been falling through the day.

Aloft, troughing is located over the northeast with broad ridging over the Plains and intermountain west. Though northwesterly flow persists aloft, surface high pressure should keep things quiet this week. Near normal temperatures are expected through Friday. From Friday onward, ensemble guidance shows a shortwave trough diving southeastward within the jet stream. Overall, the jet stream is rather weak and most guidance shows this system becoming cut off from the main flow.

Guidance can struggle in situations with a cut off low embedded within a weak steering flow. Despite this, most guidance shows this system to some extent over the weekend. Timing and location vary, but the signal is there. As such, we will carry chance to likely PoPs. A lot of details still need to be ironed out, however, given residual variability within ensemble guidance.

Beyond this weekend, ensemble guidance continues to diverge and shows no strong signal for ridging or troughing. The mean 500mb flow resides well to our north, however, so with the weekend upper low dissipating a trend towards warmer temperatures is favored for the first week of August.

AVIATION (00Z TAF Issuance)

Issued at 656 PM EDT Tue Jul 28 2026

Impacts:

- Low probability patchy fog tonight

Discussion:

Cumulus will continue to dissipate and be gone by early in the period. Any wind gusts should also be done by valid time. Elevated smoke along with a few cirrus will continue through the night, followed by a few cumulus on Wednesday.

The main question will be if any patchy ground fog develops overnight. Drier air moving in along with some light winds continuing should lower the odds for fog enough to leave mention out of the TAFs. However, can't completely rule it out.

IND WATCHES/WARNINGS/ADVISORIES

None.