Clark Mills, N.Y. — More than 8,000 Central New York residents remain without electric power as extreme heat blankets the region.

National Grid said power is projected to be restored by 11:30 p.m. Tuesday to customers still without power in Herkimer, Madison and Oneida counties. Outages in more remote areas could last until Wednesday.

About 7,100 customers were without power in Oneida County as of 10 p.m. Monday, according to the utility company’s website. Almost 1,000 were without power in Madison County, along with about 100 in Herkimer County.

Only a handful of Oneida County customers of New York State Electric & Gas, a utility company that serves fewer people, were without power as of 10 p.m. Monday.

The outages continue as much of Upstate New York is under either an extreme heat warning or a heat advisory through Wednesday.

A potentially record-breaking combination of high temperatures and humidity could make it feel like 105 degrees in the coming days, according to the National Weather Service.

Strong storms that produced a tornado, strong winds and heavy rains lashed the region Sunday. Three people died in an Oneida County hamlet after winds blew trees into homes. More than 100,000 people were left without power.

National Grid spokesperson Jared Paventi said the type of damage dealt by the storm is what is driving restoration times.

Paventi said thousands of workers, from as far away as Louisiana and the Canadian province of New Brunswick, are helping restore power.

The state Health Department has compiled a list of cooling centers. Madison County officials also have created a list of cooling centers.

Staff writer Jon Moss covers breaking news, crime and public safety. He can be reached at jmoss@syracuse.com or @mossjon7.