textproduct: Indianapolis

KEY MESSAGES

- Scattered to numerous showers and storms late tonight and Saturday. Marginally severe storms possible Saturday.

- Storm chances continue Sunday and Monday with much warmer than normal temperatures expected.

- A frontal passage Tuesday into Wednesday will bring additional chances for strong to severe storms along with cooler weather afterwards

DISCUSSION (This evening through Friday)

Issued at 221 PM EDT Fri May 15 2026

Rest of This Afternoon...

Clouds from earlier convection have been taking their time to exit the area, which has kept temperatures cooler than expected. Where sunshine has returned to the west of central Indiana, temperatures have rebounded quickly. However, will lean pessimistic and trim highs in the east.

Tonight and Saturday...

This evening will be quiet. Late tonight into Saturday morning, an upper impulse will move in from the southwest. Meanwhile, an MCS to the northwest may survive into the area or at least have impacts in the area from clouds/outflow. The upper impulse looks to have the best forcing, so will bring PoPs up to the likely category south during Saturday morning. Will keep PoPs no higher than chance north with lower likelihood that the northern MCS makes it in here.

During Saturday afternoon, uncertainty is high with a complicated setup in the area. There will be at least one boundary in the area from the morning convection. Another upper wave will move in from the west. If clouds linger longer into the afternoon, the atmosphere won't have much time to recover, and lower coverage of showers and storms will occur. If clouds clear quickly, instability will build and scattered to numerous convection will develop.

Given the high uncertainty, capped PoPs in the chance category during the afternoon and used scattered wording. If instability is able to build enough, marginally severe thunderstorms are possible.

Scattered thunderstorms will remain a threat into Saturday night with an additional upper impulse, depending on if afternoon convection consumes the instability.

Highs on Saturday will be in the upper 70s to around 80, depending on what coverage of clouds/convection occurs.

Sunday...

Heights will rise locally as upper ridging builds across the southeastern USA. This will help keep showers and storms at bay and also allow for warmer temperatures. Highs in the mid 80s should be common.

Monday and Tuesday...

Thunderstorms that develop ahead of a cold front well west of central Indiana on Monday may be able to survive into the area later Monday afternoon into evening. However, the better chances for showers and storms will be on Tuesday when the front moves into the area.

The severe threat will be mainly west of the area on Monday but will have to monitor to see if it nudges east. Depending on the timing of the front, a severe threat will exist Tuesday.

National Blended Guidance may be too warm for highs Monday, but still highs in the middle 80s are likely on Monday and perhaps Tuesday as well depending on sky cover and rain trends.

Wednesday and beyond...

Some uncertainty in timing of the front and how far south it will get leads to lingering rain chances all areas Wednesday and perhaps the far south on Thursday. At the moment, odds are high that Friday remains dry as well with high pressure still influencing the area.

Temperatures will return to closer to normal mid to late week behind the cold front.

AVIATION (18Z TAF Issuance)

Issued at 1257 PM EDT Fri May 15 2026

Impacts:

- Some gusts up to 20kt this afternoon, with gusts over 20kt Saturday - Scattered to numerous showers and some t-storms late tonight through Saturday

Discussion:

Outside of convection, VFR conditions are expected through the period. There is a low chance for a period of MVFR ceilings Saturday morning, but confidence is not high enough to include.

Clouds will gradually lift and break up this afternoon, but then increase again tonight. A complex convective threat leads to high uncertainty in timing and location of the best chances for showers and thunderstorms late tonight through Saturday.

For now believe that the best chances to see convection will be at the southern sites 10-15Z Saturday. Scattered convection would then continue through Saturday. As noted above, uncertainty is high and these times/locations will likely be refined with later forecasts.

IND WATCHES/WARNINGS/ADVISORIES

None.