Parts of the Northeast are gearing up for what could be very heavy snow Tuesday, after tornadoes and other powerful winds swept through parts of the Southern Plains and the Midwest, killing at least one person in Oklahoma, and some Michigan residents faced a sixth consecutive day without power following last week’s ice storm.

In California, the National Weather Service said winter storms will continue moving into the state through Wednesday.

A storm system produced at least four tornadoes as it moved across central and northeastern Illinois on Monday, including two that formed in suburbs west of Chicago, authorities said. Initial reports suggested damage there was limited to fallen trees or shingles torn from buildings, said Rafal Ogorek, a meteorologist in the Chicago office of the National Weather Service.

At least one person was killed and three others injured after a tornado touched down Sunday night in far western Oklahoma near the town of Cheyenne, where 20 homes were damaged and four others destroyed, Roger Mills County Emergency Manager Levi Blackketter reported.

Statewide, Oklahoma officials received reports of 55 people who suffered weather-related injuries from area hospitals.

Officials in Norman, Oklahoma, confirmed 12 weather-related injuries after tornadoes and wind gusts as high as 145 km/h (90 mph) were reported in the state Sunday night. The winds toppled trees and power lines, closed roads and damaged homes and businesses around Norman and Shawnee.

Classes were cancelled Monday at two damaged elementary schools, said Norman Police Chief Kevin Foster.

More than 76,000 customers lost power in Oklahoma, but most had it restored by Monday morning, Oklahoma’s Office of Emergency Management reported.

Blizzard warnings went into effect Monday in the Sierra Nevada range as more rounds of rain and snow moved into California and Nevada.

The new series of storms arrived even as parts of California were still digging out from last week’s powerful storm, which added to a massive snowpack left by a siege of “atmospheric rivers” in December and January.

Los Angeles County declared a cold weather alert for valley and mountain areas north of LA as overnight temperatures were expected to plunge below freezing for much of the week. Shelters were opened for residents who don’t have access to warm spaces.

A winter storm warning covered parts of the northeastern US, including Connecticut, New York, Massachusetts, New Jersey and Rhode Island, with heavy snow forecast through Tuesday afternoon.