textproduct: Indianapolis

KEY MESSAGES

- Severe weather is likely most areas today with one round of marginally severe storms in the afternoon and more widespread severe weather towards the evening. All modes of severe weather are possible

- Below normal temperatures will continue for much of the period

..SEVERE WEATHER LIKELY LATER THIS AFTERNOON INTO TONIGHT

Early This Morning...

Patchy fog will continue to develop, mainly across areas that saw rain on Tuesday. Fog may be locally dense.

Today and Tonight...

An anomalously strong system (with many variables exceeding climatological maxima for mid-June) will likely bring severe weather to central Indiana, mainly later this afternoon into the early overnight.

An initial upper wave will develop a complex of thunderstorms across Iowa and Illinois this morning, and this will spread east into central Indiana this afternoon. Increasing southwest winds thanks to a warm front moving north will bring in moisture and instability. With strong wind fields, some severe storms may be possible with this complex this afternoon, especially north near the surface warm front.

The highest PoPs will be across the northern half of the area, where better forcing will exist. The far southern forecast area may remain dry.

The strong wind field will allow a quick recovery behind this first complex. Dewpoints will rise into the 65-70 degree range. Aloft, the 850mb jet will increase to 50-60kt by 21Z. The strong wind fields will continue even farther up, creating very high shear values. As noted by the Storm Prediction Center, 0-3km shear may exceed 60kt.

Given this environment, expect supercells to develop upstream of the forecast area mid to late afternoon, and these will move into the area late afternoon into the evening hours. Some CAMs congeal these into a line, but uncertainty exists on whether this will happen given the strong shear profiles. Regardless, damaging to destructive winds, large hail, and tornadoes (some strong) are all possible with these storms.

Excellent moisture transport with this system will also lead to threat of excessive rainfall and localized flash flooding.

The storms should exit the forecast area to the south in the early overnight hours.

The wind fields will lead to near Wind Advisory criteria for much of central Indiana this afternoon and potentially into early evening. Wind gusts around 40 mph are likely, with some gusts near 45 mph possible.

Highs today will range from the upper 70s in the north where clouds and rain will be more of a factor this afternoon, to the middle 80s south where more sunshine is expected. Lows tonight will be in the 60s.

Thursday into Saturday...

A cold front just south of the area on Thursday may allow a stray shower to reach the extreme southern forecast area. Otherwise, high pressure will build in and provide dry conditions for Friday and Saturday. Some guidance does try to create some light QPF Saturday with an upper wave, but confidence is not high enough to include. Highs will near normal to below normal.

Sunday and Monday...

Models agree that a larger upper wave along with a surface low pressure system will move through the area in this time frame, but they disagree on the timing. Will keep the blended guidance's PoPs for now which peak around Sunday night, but confidence is lower than normal. High temperatures will depend on the timing of the rain, but expect near normal to below normal readings.

Tuesday and Wednesday...

Surface high pressure is expected to dominate in this period. With continued northwest flow aloft, near normal to below normal temperatures look to persist.

AVIATION (06Z TAF Issuance)

Issued at 108 AM EDT Wed Jun 17 2026

Impacts:

- Fog producing poor conditions at times overnight at KHUF/KBMG and perhaps at KLAF.

- Showers and thunderstorms this afternoon and then again this evening and overnight.

- Wind gusts over 30kt this afternoon. LLWS tonight.

Discussion:

Fog will be an issue at least at KBMG/KHUF overnight with IFR and worse conditions at times. KLAF may see some fog as well.

Otherwise, expect a complex of showers and thunderstorms to move east across most sites 18-22Z, followed by a line of convection moving from the northwest from about 23Z-06Z. IFR and worse conditions are possible, along with severe convection.

Outside of convection winds will increase this afternoon with gusts over 30kt likely. These may diminish in the evening, allowing LLWS to exist as strong winds continue aloft.

IND WATCHES/WARNINGS/ADVISORIES

None.