textproduct: Indianapolis

KEY MESSAGES

- Patchy sprinkles or light drizzle possible at times through early tonight, mainly across north-central Indiana

- Increasingly hot and humid conditions through the middle of this week

- Isolated to scattered thunderstorms will be possible at times Thursday through Saturday

DISCUSSION (This evening through Sunday)

Issued at 247 PM EDT Sun Aug 30 2026

Today through Tuesday night...

Mostly quiet conditions are expected early in the period due to surface ridging and low-level dry air in place. Current satellite and radar imagery depicts extensive mid to high clouds across northern portions of central Indiana from an approaching upper wave with some light returns. However, most of this is not reaching the ground due to dry air. Patchy sprinkles or light drizzle will be possible at times through early tonight while the impulse aloft moves through. The mid to high clouds has helped keep temperatures cooler, in the low-mid 80s, across the north.

Upper ridging building further into the Ohio Valley will likely provide quiet weather conditions through Tuesday. Guidance does suggest a few subtle impulses riding the northern periphery of the ridge, but these features should track slightly further north resulting in less than mid to high clouds than the disturbance pushing through today. That said, at least some enhancement of mid to high clouds appears likely which could limit diurnal heating slightly.

Expect southwesterly surface flow and the building upper ridge to promote warming temperatures the next few days. Look for highs to reach the upper 80s to low 90s by Monday with highs then approaching the low to mid 90s on Tuesday. Heat indices on Tuesday could be near the low 100s. A Heat Advisory may be needed for Tuesday, but will hold off for now given some forecast uncertainty.

Wednesday through Thursday...

Confidence remains higher than usual that the hot and humid conditions will persist through the middle of this week. Long range guidance depicts the aforementioned upper ridge retrograding and then amplifying across the central CONUS while troughing over the Northeast. Expect highs in the 90s with peak heat indices approaching advisory criteria. Meanwhile, lows in the 70s will provide little relief from the heat and humid.

There is some uncertainty in the forecast towards Thursday regarding max temperatures as an upper wave may move through the area as northwest flow begins to develop aloft. Anomalous moisture in place by Thursday along with sufficient forcing from the approaching disturbance supports the potential for isolated convection. A few strong storms cannot be ruled out given at least moderate destabilization and some enhancement of mid to upper level flow.

Friday into the weekend...

Confidence in exact details decreases towards the end of this week due to diverging model solutions. Long range guidance generally depicts the upper ridge across the central CONUS continuing to amplify with persistent northwest flow across central Indiana. Multiple shortwaves aloft could move through during this period supporting the potential for at least isolated convection at times. In addition, a cold front may slowly push south late Friday through the weekend. This will provide additional forcing for convection while also gradually cooling temperatures into Sunday. Greater cloud cover and low rain chances should help keep temperatures cooler as well. Look for highs mostly in the 80s to near 90F across the far south by this weekend.

AVIATION (18Z TAF Issuance)

Issued at 126 PM EDT Sun Aug 30 2026

Impacts:

- None; VFR expected.

Discussion:

VFR conditions are expected through the period. Mid and high level clouds will be expected to continue to stream across the TAF sites today. Forecast soundings continue to show dry lower levels through the next 24-36 hours. Although there are some radar returns over northern portions of central Indiana, much of this is expected to remain virga falling from high bases through dry lower levels.

Some of the moisture aloft has reached the ground with sprinkles or brief drizzle reported, mainly near KLAF. Brief sprinkles or very light drizzle cannot be ruled out through this evening, mainly near KLAF.

IND WATCHES/WARNINGS/ADVISORIES

None.