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

DISCUSSION (This evening through Wednesday)

Issued at 306 PM EDT Wed Jul 29 2026

Surface high pressure is building into the region today and a cooler and much drier air mass is now in place. Temperatures have risen into the low-mid 80s and dew points have dropped into the upper 50s in a few places. Efficient boundary layer mixing has allowed dew points to fall a bit below guidance. We're expecting similar mixing conditions on Thursday so will nudge dew points downward. Additionally, high temperatures may run a few degrees above guidance as well. Still, near to slightly below-average readings are expected.

The next few nights may see some patchy fog, which may be locally dense at times. Fog is not expected to be widespread, confined mainly to rural areas and near/along rivers. Fog may linger into the morning hours before rapidly dissipating as mixing resumes.

Aloft, troughing over the northeastern US will promote northwesterly flow across the Midwest. Ensemble guidance is in good agreement showing a shortwave trough diving southeast within this flow, arriving late Friday. A round of showers and thunderstorms is possible late Friday evening and overnight. Guidance then slows the shortwave down as western ridging amplifies. This should bring high rain probabilities into the day Saturday, potentially into early Sunday. Locally heavy rainfall amounts are possible owing to the slow system motion.

Looking into next week, the weekend shortwave departs eastward while the polar jet lifts north. Though there is no strong signal for either troughing or ridging, the jet stream residing well to our north should allow temperatures to creep upwards. A warming trend is therefore favored next week with highs potentially reaching into the upper 80s / near 90 at times. Some guidance keeps the jet stream active, with frequent storm systems embedded within the broader flow. This may act to keep daily precipitation chances above average through next week as well. However, the signal regarding precipitation is less clear than for temperatures.

AVIATION (18Z TAF Issuance)

Issued at 133 PM EDT Wed Jul 29 2026

Impacts:

- Low probability patchy fog tonight

Discussion:

Cumulus have developed this afternoon and may oscillate between SCT and BKN at times. Cloud bases around 3500 to 5000 ft agl are expected. Cumulus will dissipate after 00z.

There is a low chance of patchy fog overnight tonight, particularly at LAF. Probabilities are quite low and fog will not be included as a prevailing group in the TAFs for now.

Thursday looks to be similar to today with diurnal cumulus and a light northerly wind. Winds may become light and variable tonight onward as the center of surface high pressure moves overhead.

IND WATCHES/WARNINGS/ADVISORIES

None.