Indianapolis woke up in a sweat on Wednesday, July 15, with clear skies, sticky humidity and temperatures already in the low 70s after a warm night that never really cooled off. Forecasters say the heat will only build from here, with a high near 94°F and another muggy night stuck in the mid 70s. Anyone working or playing outside should plan for serious heat, drink plenty of water and take regular breaks during the midafternoon peak.
Heat Advisory From Noon To 8 p.m. Wednesday
The National Weather Service has a Heat Advisory in effect for Marion County from noon to 8 p.m. EDT on Wednesday, July 15, warning that heat index values could push around 100°F this afternoon. Expect mostly sunny skies and light west winds around 1 to 5 mph during the hottest part of the day. For the full forecast and hourly breakdown, check NWS Indianapolis.
Air Quality And Knozone Action Day
The Office of Sustainability has also called a Knozone Action Day, in effect from midnight tonight through midnight Wednesday night, as the heat and light winds are expected to drive ground-level ozone into the "Unhealthy for Sensitive Groups" range. Active children, older adults and anyone with respiratory conditions are urged to limit prolonged outdoor exertion and follow recommended steps to cut emissions, such as consolidating car trips and avoiding unnecessary engine idling. More details and hourly air-quality guidance are available from IDEM SmogWatch.
Storm Chances Toward The Weekend
High pressure will keep most of the heat dry through Thursday, but the pattern shifts late in the week and showers and thunderstorms move in on Friday. Forecasts currently show about an 80% chance of rain Friday, with new rainfall amounts around a quarter to a half inch possible and isolated heavier downpours in stronger storms, according to NWS Indianapolis. If you have outdoor plans, it is worth keeping an eye on updates as the end of the week approaches.
Cooling Centers And Safety Tips
For anyone who needs a place to cool off, Indy Parks family centers and Indianapolis Public Library branches are open as public cooling centers during extreme heat events, and many list their hours and locations online. You can call 2-1-1, check city resources, or go directly to the Indy Parks cooling-center list at Indy Parks for addresses and hours. Outdoor workers should take frequent water breaks, rest in the shade when possible and slow activity during the midafternoon peak when conditions are most dangerous.
For background on how this heat pattern developed, see Indy swelters as brutal heat advisory clamps city through Thursday (June 29 coverage). This update zeroes in on today's advisory and the air-quality action day that could hit sensitive residents the hardest.
