Follow live updates as a winter storm is expected to bring heavy snowfall, icy roads and cold temperatures across the United States.

Major winter storm expected to impact 235 million Americans this weekend with thousands of flight cancellations anticipated across major airlines nationwide.

The National Weather Service issues a litany of notices before and during inclement weather events. They can be important signals on how to respond.

On Saturday at 5:07 a.m. EST a winter weather advisory was issued by the National Weather Service valid from 7 p.m. EST until Monday 1 a.m. EST for Branch and Hillsdale counties.

This index, from NOAA's National Weather Service, attempts to scale the impacts from winter weather, taking into account factors such as snowfall, accumulated snow on rooftops, ice accumulation, the potential for a flash freeze, and blowing snow. Not all factors are in play in a given winter storm.

ERCOT, which operates the Texas power grid, has issued an advisory for "extreme cold weather" in Texas. TEXAS, USA — The Electric Reliability Council of Texas (ERCOT) has issued an advisory for "extreme cold weather" ahead of the expected winter storm in Texas this weekend.

The National Weather Service released a winter weather advisory at 2:52 p.m. EST on Saturday valid from 10 p.m. EST until Sunday 10 p.m. EST for Eaton, Van Buren and Kalamazoo counties.

Here's what to know before the storm hits. According to the American Red Cross, here is what should be in your emergency preparedness kit: If the power is out for less than two hours, perishable food should still be safe to consume.