textproduct: Indianapolis

KEY MESSAGES

- Scattered showers/t-storms possible late this afternoon and overnight. Gusty winds and localized flooding possible.

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

- Thunderstorms likely again late Thursday into Thursday night. Strong to severe storms possible.

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

DISCUSSION (Today through Tuesday)

Issued at 311 AM EDT Wed Jun 10 2026

The pattern aloft is characterized by anomalous ridging over the eastern US and into Canada with troughing over the western US. A slow-moving vort max displaced from the jet stream meanders over the Great Lakes. This feature is what has been bringing the near daily rain chances to Indiana lately. As the western trough moves eastward, the vort max will eject northeastward. Southwesterly aloft then intensifies and a warming trend is expected for Wednesday and Thursday.

High temperatures today and tomorrow will be near 90, with dew points into the low to mid 70s. Heat indices between 100 and 105 are possible, which may lead to enhanced heat risk for vulnerable populations.

Showers and thunderstorms are possible once again today, mainly in the afternoon and evening hours. Despite minimal forcing, it doesn't take much in such a humid environment to generate some convective activity. Buoyant forces alone can get the job done. However, since this is the case it will be hard to pin point exactly where these showers/storms develop. Activity likely remains isolated to scattered during the afternoon.

Things change as we head into tonight. Convection initiated from the approaching trough may propagate southeastward out of Illinois. This activity is likely to be more organized, especially if it develops a cold pool and can consolidate into a line. Guidance does not indicate an abundance of shear, so any line of storms may tend to become outflow dominant as it heads deeper into Indiana. Strong gusty winds are possible before this happens. Additionally, given recent rainfall a flooding threat could again materialize.

Another round of convection associated with a wave ejecting from the broader trough looks to arrive late Thursday. Guidance shows a bit more energy in the atmosphere which could lead to severe thunderstorms at times, especially northwestern portions of central Indiana. Like Wednesday evening, storms likely become outflow dominant as they head southeast away from the best forcing and shear. Strong to severe wind gusts and localized flooding are the primary hazards.

Once that system and its cold front pass through late Thursday night, a transition to a cooler and less active pattern appears likely. Broad troughing aloft looks to persist this weekend and into next week, with near-average temperatures (highs near 80 and lows near 60) along with lower humidity. A few weak waves embedded within the broader trough may bring rain chances on Sunday and then again on Tuesday or Wednesday of next week. These are subtle features and are hard to pin point this far out. So we will maintain only chance PoPs next week until the signal become clearer.

AVIATION (12Z TAF Issuance)

Issued at 636 AM EDT Wed Jun 10 2026

Impacts:

-Gusty winds from SW Wednesday afternoon, between 20-25kt.

-Showers/storm chances return after 22z.

Discussion:

Skies have cleared which has allowed patchy fog to develop. Fog has been dense at times and may ebb and flow through sunrise. Any lingering fog will quickly dissipate early this morning.

SW winds pick up today as low pressure passes to our northwest. Gusts up to 25 knots are possible at times during the afternoon hours.

Showers and thunderstorms may redevelop during the late afternoon, but overall chances are low. Will add another Prob30 group to account for this. Additionally, showers/storms may continue into the night as activity from the low pressure to our northwest spreads southeastward. Showers and storms come to and by 12z Thursday morning.

IND WATCHES/WARNINGS/ADVISORIES

None.