(CNN)Two powerful storms are leaving much of the United States struggling with blackouts, whiteouts and gusty winds on Thanksgiving Day -- and the nightmare could continue in some areas into the holiday weekend.
The weather was so chaotic with both storms, at one point 32 states were under some sort of watch, warning or weather advisory.
One system pounded the Western states with rain along the coast and heavy snow in the mountains. While on the other coast, another storm dumped snow and high winds knocked out power. At one point Wednesday night, nearly 300,000 homes and businesses were without power nationwide, mainly in Michigan, Ohio and California, according to utility tracking site poweroutage.us.
The weather pattern remains active going into the holiday weekend, the National Weather Service said.
"Widespread winter weather, flash flood and wind watches, warnings and advisories are currently in effect ... across large portions of the nation," it said.
By early Thursday, more than 200 flights had been canceled in the United States and nearly 2,000 delayed, according to FlightAware.
Millions under threat
The storm in the western US has left more than 20 million people under a winter threat, CNN meteorologist Gene Norman said.
As it moves toward the East Coast on Saturday and Sunday, it could mess up travel until the Monday commute after bringing an icing threat in the middle of the country Thursday and Friday, he said.
"Thanksgiving 2019 will be remembered as a stormy day for many in the West. A cornucopia of hazards will continue to develop eastward across the country through the weekend," the National Weather Service said.
Winter storm watches, warnings and advisories touch parts of every western state from Arizona to Montana. The storm set November low-pressure records in parts of Oregon and Northern California, the National Weather Service said.
In Arizona, the weather service warned of "impossible travel conditions" Thursday and early Friday with heavy and drifting snow.
Heavy rains will also pose a flash-flooding threat in Southern California through Thanksgiving, and in the Southwest by early Friday, the weather service said.
In Santa Barbara County, officials warned that heavy rain could cause dangerous debris flows near areas burned this week by the Cave Fire. "If a debris flow occurs, and it is unsafe to leave, or you are unable to leave, go to high ground," the county said.
Thanksgiving Day Parade
The weather might have an affect on an iconic annual tradition. New York Mayor Bill de Blasio hopes it won't ground balloons in Macy's Thanksgiving Day Parade.
"I'm keeping my fingers crossed, I'm asking everyone -- keep the City of New York in your thoughts and prayers so the wind will stay calm and we will be able to let these balloons fly," De Blasio said Wednesday as the balloons were being inflated. "We're hopeful. We're hopeful."
The balloons can't be flown when sustained winds exceed 23 mph and gusts exceed 34 mph, per New York City regulations. In 1997, the Cat in the Hat balloon injured four people after intense winds forced it astray.
CNN's Christina Maxouris, Amanda Watts, Judson Jones, Holly Yan and Joe Sutton contributed to this report.