* WHAT. Dangerously hot conditions with heat index values of 110 to 115 possible. * WHERE. Portions of east central and northeast Illinois and northwest Indiana. * WHEN. From Tuesday afternoon through Tuesday evening. * IMPACTS. Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities.

* WHAT. Dangerously hot conditions with heat index values of 110 to 115 possible. * WHERE. Portions of east central and northeast Illinois and northwest Indiana. * WHEN. From Tuesday afternoon through Tuesday evening. * IMPACTS. Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities.

* WHAT. Dangerously hot conditions with heat index values around or greater than 105. * WHERE. Portions of northern Indiana, southwest Michigan and northwest Ohio. * WHEN. From Tuesday morning through Tuesday evening. * IMPACTS. Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities. * ADDITIONAL DETAILS. There is the chance that thunderstorms and/or clouds could cut into how high temperatures get across the area, but it is still expected to be warm and humid. Overnight heat indices Tuesday morning and Tuesday night bottoming out around 75 will make it harder for those affected by heat related conditions to recover, especially without air conditioning.