Here’s what a heat dome is, how it’s different from a heat wave and how hot it has to get for each region of Florida to issue a heat advisory.

The National Weather Service has issued severe thunderstorm warnings for New York City and parts of the Hudson Valley, New Jersey and Connecticut, with expected wind gusts of up to 70 mph and potential hail. After several mild summer weather days, the excessive heat has returned. Additionally, severe weather could be a factor for some Friday night.