The National Weather Service forecast up to 4 feet of snow or more through Sunday that “may paralyze” the hardest-hit communities, including Buffalo, with periods of near-zero visibility.
Hochul's state of emergency covers 11 counties, with commercial truck traffic banned from a stretch of Interstate 90 southwest of Buffalo after 4 p.m. Thursday.
The snowfall was expected to be at its greatest intensity between 7 p.m. Thursday and 7 p.m. Friday.
“I want western New Yorkers to take this seriously,” Hochul said.
The weather service also warned of accumulations of 2 feet or more of lake-effect snow in parts of northern Michigan through Sunday.