Back-to-back storms left 15 inches (38 centimetres) of snow in Little Rock, Arkansas, tying a 1918 record, the National Weather Service said.
At least 24 people have died this week, some from fires or carbon monoxide poisoning while trying to stay warm in their homes, according to the Associated Press. Elsewhere, a grandmother and three children died when flames escaped the fireplace they were using to keep warm.
Winter storms during the past week in the Midwest, Texas and the South forced water service providers to scramble to manage flows as sub-freezing temperatures presented serious problems.
A historic winter weather system that brought bitter, record-busting cold to much of the southern and central United States was pushing up the East Coast yesterday, with forecasters warning of heavy snowfall and risky, icy build-ups.
Texas officials ordered seven million people - a quarter of the population of the nation's second largest state - to boil tap water before drinking it following days of record low temperatures that have damaged infrastructure and frozen pipes.
St. David's HealthCare said in a statement to CBS News on Thursday that its South Austin Medical Center lost water pressure and was restricting water usage.
In addition to aiding Texas, FEMA said on Thursday it would provide assistance to the neighboring state of Oklahoma due to the weather's impact on its power grid.
Compounding the misery, thousands of Houston residents were also suffering a loss of water pressure.
"Because this is a state-wide emergency situation that is also impacting other hospitals within the Austin area, no one hospital now has the capacity to accept transport of a large number of patients", St David's South Austin Medical Center CEO David Huffstutler said in a statement.
Public works crews work to fix broken water lines in Wylie, Texas on Thursday, February, 18, 2021.
Millions of Texans must boil water, hundreds of thousands still without power due to winter storm
Texas Governor Greg Abbott said: "About 1,600,000 homes have had power restored today".
Weather-related outages have been particularly stubborn in OR, where some customers have been without power for nearly a week. A Portland supermarket threw perishable food into the trash, leading to a clash between scavengers and police.
A woman collects ice cream that had been thrown out because of power outages at a Kroger store in Arlington, Tex.
Judge Lina Hidalgo, the top elected official in Harris County, which encompasses Houston, said that the number of homes without power in her county had fallen to 46,000 from almost a million the previous night. At the peak of the storm, more than 350,000 customers in the Portland area were in the dark. More than 100,000 customers in OR remained without power Thursday.
"ERCOT was able to direct utilities to restore 600,000 households last night".
In this photo provided by Amber Moore, damage to a house from a downed tree is seen in Lake Oswego, Ore.
Power plant operators could have negotiated gas-supply contracts with extra reserves to maintain operations during extreme weather, he said, but that would have raised their costs.
Texas power companies had to implement rolling blackouts to avoid grids being overloaded as residents cranked up the heat.
Louisiana governor John Bel Edwards sought a presidential emergency declaration on Wednesday evening, seeking federal money and supplies in response to extended power cuts in his state. Power is slowly being restored to homes.
"We have been caught in the middle of something here where there have been individuals who have not had electricity or power for about three and a half days now [and] it's zero degrees", Evans said of Mansfield, a suburb in the Dallas-Fort Worth area.