textproduct: Indianapolis

KEY MESSAGES

- Rain and storm chances return tonight through the weekend

- Heavy rainfall and flash flooding a primary concern late Thursday through Saturday with 1-3 inches of rain possible

- Hot and humid conditions expected for much of next week with multiple days in the 90s

DISCUSSION (This evening through Wednesday)

Issued at 309 PM EDT Wed Jun 24 2026

This afternoon through Wednesday...

Quiet weather conditions are ongoing as surface high pressure continues to shift east across the region. Latest satellite imagery depicts increasing mid to high clouds from the northwest. These clouds are associated with a low amplitude wave aloft and an associated weak surface surface low will move into the region this evening into the overnight hours.

Modest moisture advection combined with sufficient forcing supports the potential for some convection. However, uncertainty remains on convective coverage as a lingering dry airmass will take time to saturate. Recent CAMs support this showing incoming convection dissipating as it pushes southeastward at least initially. Once top- down saturation occurs, isolated to scattered convection can be expected during the overnight period.

Temperatures have already warmed into the mid to upper 70s thanks to return flow and plentiful sunshine. Look for milder lows tonight in the low to mid 60s as cloud cover increases.

Thursday through Saturday night...

Model guidance suggest the front associated with the aforementioned low pressure system should still be situated across central Indiana though uncertainty remains on exactly where the boundary will be located. Daytime heating along with moisture advection ahead of the front supports the potential for scattered convection to develop during the afternoon hours Thursday.

Favorable deep-layer wind shear above a moderately unstable environment suggest isolated strong to severe storms are possible. The primary threats are isolated damaging wind gusts and large hail. Tornadoes appear unlikely given weak low-level wind shear. The severe weather threat is mainly focused over south-central IN as the front may move across northern portions of the forecast area before sufficient destabilization occurs.

The front may be briefly shunted further south Thursday night if sufficient cold pool development occurs. This would limit storm chances before the front then lifts back north early Friday. Guidance continues to suggest multiple waves tracking across the meandering boundary Friday and Saturday. Widespread precipitation is expected Friday and Friday night with additional chances for convection through Saturday night. The greatest rain chances are focused across the southern half of the forecast area where the strongest forcing and deeper moisture overlap.

Deeper moisture lifting north along with the potential for repeated rounds of storms supports an elevated flash flooding threat, primarily Friday and Friday night. Modest enhancement of mid-upper level flow on top of a modest-moderately unstable environment may promote additional marginal severe threats, but widespread severe weather appears unlikely.

Sunday onward...

Rain chances diminish Sunday as long range guidance depicts an amplifying upper level ridge shifting eastward into eastern portions of the CONUS. The ridge axis should be centered over the region late Sunday into Monday and remain persistent through at least the middle of next week before possibly retrograding. This will likely promote hot and humid conditions Sunday through much of the following week. Mostly dry conditions are also expected due to large scale subsidence. Weak impulses riding the northern periphery of the ridge may support a chance for convection at some point next week depending on the location of the upper ridge, but this appears unlikely at this time. Some uncertainty remains on exactly how hot temperatures will get given dewpoints will be well into the 70s, but highs approaching the low 90s appear increasingly likely by early next week. These temperatures combined with dewpoints in the 70s could lead to potentially dangerous heat indices approaching Advisory criteria.

AVIATION (00Z TAF Issuance)

Issued at 717 PM EDT Wed Jun 24 2026

Impacts:

- Isolated to scattered showers and possibly a thunderstorm may impact terminals tonight

- Additional storms possible Thursday afternoon

Discussion:

Predominantly VFR conditions expected through the period, outside of any possible impacts from convection.

Isolated to scattered showers and storms are occurring upstream, and though what limited instability is available will be waning diurnally, some activity may survive into the area later tonight. Will carry PROB30 groups for showers at each site for a period late tonight into early Thursday morning. A rumble of thunder will be possible but far too uncertain and low probability for mention.

Broken VFR ceiling will continue into Thursday, with increasing chances for showers and perhaps a few storms as an upper level wave moves through the Great Lakes and a diffuse frontal zone sags into the region. Will again carry PROB30 groups, this time for -TSRA, at all but LAF which should be farthest removed from the boundary during the most favorable timing for convection.

Winds will be 10KT or less through the period, from 190-210 early, becoming from 240-270 late tonight into Thursday.

Any obstructions to visibility will likely be primarily tied to convection impacts.

IND WATCHES/WARNINGS/ADVISORIES

None.