textproduct: Indianapolis

KEY MESSAGES

- Hot and humid today. Heat indices between 100 and 105 degrees.

- Thunderstorms likely again late tonight. Strong to severe storms possible, especially across northwestern portions of central Indiana.

- Slightly cooler weather for the weekend with near average temperatures.

- Showers and thunderstorms possible on Sunday.

MESOSCALE UPDATE

Issued at 614 PM EDT Thu Jun 11 2026

A weak and somewhat diffuse boundary extends across central Indiana at 22Z, roughly from near Rockville to not far southwest of Indy then continuing to the southeast. Winds temporarily backed to southeast at Terre Haute last hour and are currently southeast at Bloomington.

Isolated convection has been developing near the boundary, but most convection hasn't become strong due to a weakening cap aloft (per IND ACARS sounding). Still, an earlier cell did become stronger and showed some broad rotation.

With MLCAPE of 3000-4000 J/kg and some shear, expect cells to continue to pop up as the boundary gradually shifts northeast. With the weak cap, most cells should remain weak or at least sub-severe. However, if one can get going, it could rotate and severe weather would become possible.

The main event will still be late this evening into the overnight with a line of convection moving through. There still remains some uncertainty on the precise timing. Latest WoFS runs are showing the main line impacting the area mainly after 02Z (10 PM), but will continue to monitor closely.

DISCUSSION (This evening through Thursday)

Issued at 330 PM EDT Thu Jun 11 2026

Heat and humidity continue today with heat indices near 100 degrees this afternoon. Behind a cold front, which will bring a line of showers and thunderstorms tonight, some relief to the hot conditions will arrive.

Tonight's round of convection will also be spurred on by a wave ejecting from the broader trough aloft. Recent CAM runs continue to slow the line down despite lagging slightly from where storms are actively ongoing to our northwest. Still can't rule out the line slowing some between now and tonight, but will keep with the arrival timing between 8pm and 10pm rather than later. Guidance continues to show a bit more energy in the atmosphere which could lead to severe thunderstorms at times, especially northwestern portions of central Indiana. Like last night, storms will likely become outflow dominant as they head southeast away from the best forcing and shear, but damaging wind gusts will again be the main threat as storms decay over our forecast area. Localized flooding may also be a concern in heavier storms. Storms are expected to weaken by around 2am followed by rain and the associated cold front exiting to the SE by tomorrow morning.

Behind the front, central Indiana will see some relief for the weekend. Another system will likely bring additional showers and storms Saturday night to Sunday morning followed by further heat and humidity relief going into the start of next week.

AVIATION (00Z TAF Issuance)

Issued at 703 PM EDT Thu Jun 11 2026

Impacts:

- Wind gusts near 25kt possible this evening

- Isolated convection early, then thunderstorms move through 02Z-08Z. MVFR and and worse conditions in convection.

- Winds become northwest overnight behind a cold front

Discussion:

Isolated convection may be around to start the period, but areas of convection will arrive in the the northwest around 02Z then gradually spread south and east across the sites. Convection should be gone by 08-09Z. Some uncertainty remains on the precise timing but will use TEMPOs with the most likely periods.

Behind the convection there may be a brief period of MVFR ceilings. Otherwise outside of convection VFR conditions are expected through Friday.

IND WATCHES/WARNINGS/ADVISORIES

None.