A lake-effect storm blanketed parts of the Great Lakes region with snow on Friday, closing highways on one of the biggest travel weekends of the year. Gov. Kathy Hochul of New York declared a state of emergency in 11 counties.

The storm had already brought more than eight inches of snow to portions of Marquette County in Michigan’s Upper Peninsula by Friday afternoon, according to the National Weather Service.

Portions of Western New York, such as Mayville on the northern end of Chautauqua Lake about 22 miles north of Jamestown, had recorded 17 inches of snow by midafternoon on Friday, according to forecasters.

Watertown, N.Y., where less than an inch of snow had fallen on Friday afternoon, was forecast to get close to six feet of snow over the next three days.

“We are so accustomed to this kind of storm,” Ms. Hochul said in an interview with Spectrum News on Friday. “We don’t love it, but it is part of who we are as New Yorkers, especially western New York and the North Country.”

The National Weather Service in Buffalo said the prolonged lake-effect snow “will bury some areas east of both Lakes Erie and Ontario.”