At 216 PM EDT, a rapidly developing thunderstorm was located near Morrow, moving east at 20 mph. HAZARD. Wind gusts up to 40 mph and very heavy rain. SOURCE. Radar indicated. IMPACT. Gusty winds could knock down tree limbs and blow around unsecured objects. Visibility will be poor and hydroplaning is possible. Locations impacted include. Wilmington, Blanchester, New Vienna, Morrow, Clarksville, Harveysburg, Martinsville, Corwin, Midland, Port William, Butlerville, Paintersville, Melvin, State Route 123 at State Route 132, Fort Ancient, Lumberton, Oakland, Caesar Creek State Park, Morrisville, and Ogden. This includes I-71 in Ohio between mile markers 34 and 57. If outdoors, consider seeking shelter inside a sturdy building. Motorists should slow down and use extra caution. To report hazardous weather conditions, go to our website at weather.gov/iln and submit your report via social media, when you can do so safely.

At 214 PM EDT, Doppler radar was tracking a strong thunderstorm near Morral, or 8 miles southwest of Bucyrus, moving northeast at 15 mph. HAZARD. Wind gusts up to 50 mph and penny size hail. SOURCE. Radar indicated. IMPACT. Gusty winds could knock down tree limbs and blow around unsecured objects. Minor hail damage to vegetation is possible. Locations impacted include. Bucyrus, Galion, Crestline, Morral, Tiro, North Robinson, and Sulpher Springs.

At 203 PM EDT, a rapidly developing thunderstorm was located over Fairborn, moving east at 25 mph. HAZARD. Wind gusts up to 40 mph and very heavy rain. SOURCE. Radar indicated. IMPACT. Gusty winds could knock down tree limbs and blow around unsecured objects. Visibility will be poor and hydroplaning is possible. Locations impacted include. Springfield, Beavercreek, Huber Heights, Fairborn, Xenia, Yellow Springs, Wright-Patterson Afb, Cedarville, Enon, South Charleston, Wilberforce, Harmony, Lisbon, South Vienna, South Solon, Clifton, Green Meadows, Hustead, Selma, and Oldtown. This includes I-70 in Ohio between mile markers 42 and 65. If outdoors, consider seeking shelter inside a sturdy building. Motorists should slow down and use extra caution. To report hazardous weather conditions, go to our website at weather.gov/iln and submit your report via social media, when you can do so safely.

At 147 PM EDT, Doppler radar was tracking strong thunderstorms along a line extending from 6 miles south of Wakeman to near New London to near Shelby. Movement was east at 20 mph. HAZARD. Wind gusts up to 40 mph and half inch hail. SOURCE. Radar indicated. IMPACT. Gusty winds could knock down tree limbs and blow around unsecured objects. Minor hail damage to vegetation is possible. Locations impacted include. Grafton, Wellington, New London, Savannah, Polk, Sullivan, Lagrange, Penfield, Pittsfield, Greenwich, Spencer, Bailey Lakes, Rochester, Nova, and Valley City.

* WHAT. Heat index values of 100 to 104 expected. * WHERE. Portions of east central Ohio, northwest, southwest, and western Pennsylvania, and northern and the northern panhandle of West Virginia. * WHEN. Until 8 PM EDT Friday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses.

* WHAT. Heat index values of 100 to 104 degrees are expected at times this week with variability each day due to clouds and scattered showers and storms, especially early in the week. * WHERE. Portions of north central, northeast, and northwest Ohio and northwest Pennsylvania. * WHEN. Until 8 PM EDT Friday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses.

* WHAT. Heat index values up to 101 are expected. * WHERE. Portions of east central and southeast Indiana, northeast and northern Kentucky, and central, south central, southwest, and west central Ohio. * WHEN. Until 8 PM Friday. * IMPACTS. The combination of excessive heat due to temperatures in the 90s and high humidity will increase the threat of heat illnesses.

* WHAT. Heat index values up to 103 expected. * WHERE. Portions of northeast Kentucky, southeast Ohio, and central, northern, southern, and western West Virginia. * WHEN. Until 8 PM EDT Friday. * IMPACTS. Hot temperatures and high humidity may cause heat illnesses.

The Miami Valley Regional Planning Commission and the Regional Air Pollution Control Agency have issued an Air Quality Alert for Montgomery, Miami, Greene, Clark, Preble and Darke counties in the Miami Valley Region, until midnight EDT tonight. Levels of ozone within the region may approach or exceed unhealthy standards. On Alert days, help reduce ozone by taking the following actions: * Carpool, if possible, bike, walk or take the bus instead of driving alone. * Refuel your vehicle after 8 pm. * Do not idle your vehicle, exhaust contributes to air pollution. * Mow your lawn in the evening hours and avoid the use of gas-powered lawn equipment. For additional actions and information, visit miamivalleyair.org or call 937-223-6323