Westchester County is preparing for a significant winter storm and extreme cold with a state of emergency set to begin Saturday.

Westchester County Executive Ken Jenkins said the county will enter a state of emergency starting at 6 p.m. Saturday and continuing for five days because of expected road conditions.

He says a winter storm watch is in effect from 3 a.m. Sunday through 6 p.m. Monday, and a cold weather advisory runs from 10 p.m. Thursday to 10 a.m. Friday, with very cold conditions expected to continue into next week.

Jenkins is also urging residents to stay off the roads Sunday and until conditions improve Monday and to prepare vehicles with emergency supplies.

He also says residents should fully charge electric vehicles and phones ahead of the storm in case of power outages. He also encouraged residents to download utility company apps, sign up for alerts, and use county and department apps and websites for road, transit and service updates, including possible Bee-Line Bus route changes, airport travel impacts and road clearing operations.

Residents are reminded to use generators only outdoors and at least 20 feet away from homes and to make sure carbon monoxide detectors have fresh batteries. Jenkins also stressed preparing pets for cold weather and cleaning paws after they come inside because of snow, ice and salt.

Westchester County Commissioner of Emergency Services Susan Spear says the storm could bring up to a foot or more of snow starting early Sunday and continuing overnight into Monday. She says the heaviest snowfall is expected Sunday afternoon, with possible whiteout conditions and ice making the storm more dangerous.

Spear said the storm could impact power lines and make travel, walking and shoveling treacherous as temperatures drop well below freezing into next week. She said county departments are coordinating with police, public works and transportation agencies, with additional 911 dispatchers on staff and emergency equipment prepared.