(CNN) Millions of people have been soaked by downpours, left in the dark or forced to shovel snow as powerful storms barrel through much of the US ahead of Thanksgiving.

Two massive systems were making it difficult for travelers taking to the roads and skies on Thanksgiving Eve . A combination of snow, rain and high winds has 32 states under some sort of watch, warning or weather advisory.

One system is hammering the Western states with rain along the coast and heavy snow in the mountains; on the other coast, high winds are knocking out power while New England and Maine residents brace for heavy snow.

City officials declared a snow emergency in Minneapolis and St. Paul, Minnesotta on Wednesday.

Ahead of Thanksgiving, New York Mayor Bill de Blasio said he is keeping his fingers crossed that the storm 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."

Photos: Windy conditions might ground these Thanksgiving balloons Balloons for the Aflac Duck and Macy's are ready to go for the annual Macy's Thanksgiving Day Parade. But windy conditions could keep them out of the sky on Thursday. Hide Caption 1 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Police officers stand guard as people watch the balloons get inflated on Wednesday. Hide Caption 2 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Yayoi Kusama's "Love Flies Up to the Sky" balloon is seen on Wednesday. Hide Caption 3 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Workers inflate the Pillsbury Doughboy balloon. Hide Caption 4 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Crowds watch as the balloons are inflated. Hide Caption 5 of 19 Photos: Windy conditions might ground these Thanksgiving balloons The Trolls balloon is kept under a net during the inflation process. Hide Caption 6 of 19 Photos: Windy conditions might ground these Thanksgiving balloons The Macy's Thanksgiving Day Parade has been a holiday tradition for nearly a century. Hide Caption 7 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Children watch parade volunteers work on balloons Wednesday. Hide Caption 8 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Parade volunteers work on the Trolls balloon. Hide Caption 9 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Workers carry a helium hose as the "Diary of a Wimpy Kid" balloon is inflated. Hide Caption 10 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Olaf, a character from Disney's "Frozen," is readied for the parade. Hide Caption 11 of 19 Photos: Windy conditions might ground these Thanksgiving balloons The Grinch balloon is secured. Hide Caption 12 of 19 Photos: Windy conditions might ground these Thanksgiving balloons A man works near the Ronald McDonald balloon. Hide Caption 13 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Parade volunteers work on the Trolls balloon. Hide Caption 14 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Pikachu's balloon is ready to fly. Hide Caption 15 of 19 Photos: Windy conditions might ground these Thanksgiving balloons A "SpongeBob SquarePants" balloon is kept under a net after being inflated. Hide Caption 16 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Parade volunteers work on a Wiggle Worm balloon. Hide Caption 17 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Astronaut Snoopy might not get liftoff if the winds are too strong on Thursday. Hide Caption 18 of 19 Photos: Windy conditions might ground these Thanksgiving balloons Dinosaur balloons are prepared for the parade. Hide Caption 19 of 19

The balloons can't be flown when sustained winds exceed 23 mph and gusts exceed 34 mph, per New York City regulations. There's good reason for that. In 1997, the Cat in the Hat balloon injured four people after intense winds forced it astray.

High winds -- with gusts above 35 mph in several places, including San Francisco, the Sierra Nevada range, Chicago and Cleveland -- are causing widespread power outages and winds are expected to push northeast overnight. Wind advisories across the country cover nearly 90 million people.

Nearly 300,000 homes and businesses were without power across the country Wednesday. As of 7 p.m. ET, most of the outages were in Michigan, Ohio and California, according to utility tracking site poweroutage.us

Powerful winds and heavy rain in the West

A bomb cyclone -- a type of rapidly strengthening storm -- began dumping rain over parts of the West on Tuesday night, and more rainfall is expected through Thanksgiving. Winter storm watches, warnings and advisories touch parts of every western state from Arizona to Montana.

The storm was "historic" and "unprecedented" because it set November low-pressure records in parts of Oregon and Northern California, the National Weather Service said

Lower pressure typically will yield strong winds -- as this storm did. Hurricane-strength winds -- sustained winds of 85 mph and gusts to 106 mph -- hit Cape Blanco, Oregon, on Tuesday afternoon, the weather service said.

The system has weakened some, but "it remains a very large system with impacts expected across a large portion of the nation to the west of the Rockies over the next several days," the weather service said Wednesday afternoon.

In this still image taken from a Caltrans remote video traffic camera, eastbound Interstate 80 is empty Wednesday morning because of closures and restrictions in Soda Springs, California.

There were reports of heavy snow -- with some mountain ranges in eastern California measuring snow piles in feet Wednesday, the weather service said.

Significant travel delays and road closures because of dangerous travel conditions were also expected across California, the service said.

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 at and below the areas burned this week by the Cave Fire . "If you live or are near creeks and streams be aware that they may experience high flows and can rise quickly. If a debris flow occurs, and it is unsafe to leave, or you are unable to leave, go to high ground," the county said.

Heavy snow and high winds stretch to Northeast

Another major storm has Midwest residents digging out from snow-covered cars and sidewalks and struggling with slick roads.

The city of Minneapolis declared a snow emergency due to the blizzard conditions. More than 7 inches of snow have fallen since midnight, making it the biggest Thanksgiving eve storm in decades, the weather service said.

A man plows snow Wednesday after a blizzard struck Minneapolis.

Parts of Michigan have seen 15 inches of snow and nearly 14 inches were reported in Wisconsin.

The storm had unleashed powerful winds, snow and rain over the Plains before moving over the upper Midwest on Wednesday, dumping snow from Nebraska to Wisconsin, CNN meteorologist Michael Guy said.

It will continue moving north and east, not only bringing snowfall but fierce winds to the Great Lakes and into the Northeast before exiting into the Atlantic by Thanksgiving morning.