PHOENIX (ASSOCIATED PRESS) - Wintry weather bedevilled Thanksgiving weekend travellers across the United States on Saturday (Nov 30) as a powerful and dangerous storm moved eastward, dumping heavy snow from parts of California to the northern Midwest and inundating other areas with rain.
The authorities found the bodies of two young children, including a five-year-old boy, and a third child was missing in central Arizona after a vehicle was swept away while attempting to cross a runoff-swollen creek.
A storm-related death also was reported in South Dakota.
The National Weather Service said the storm was expected to drop 15cm to 30cm of snow from the northern Plains states into Minnesota, Wisconsin and Upper Michigan.
Blizzard conditions early on Saturday were already buffeting the High Plains. The city of Duluth, Minnesota, issued a "no travel advisory" beginning at noon on Saturday because of a major snow storm it termed historic.
Duluth officials asked the public to be patient as ploughs clear roadways, and recommended that drivers stay off the roads to prevent accidents and let officers respond more quickly to emergencies.
Farther south, rain and thunderstorms were forecast along and ahead of the cold front.
Forecasters said a new storm is expected to bring California several feet of mountain snow, rain and gusty winds through the weekend. Another system is forecast to develop in the mid-Atlantic on Sunday, moving as a northeaster into Monday.
Airlines at O'Hare International and Midway International in Chicago reported average delays of 15 minutes as a winter storm headed towards the Midwest with heavy snow and ice and gusty winds.
The companies said they had cancelled 27 flights at O'Hare and two at Midway as people scrambled to get home on the year's busiest travel weekend.
At Denver International Airport, there were 100 flights cancelled on Saturday because of high winds.
"Tomorrow (Sunday), the airlines anticipate to be the busiest travel day of the Thanksgiving period at both O'Hare and Midway," said Ms Karen Pride, a spokesman for the Chicago Department of Aviation. "Everybody thinks the day before Thanksgiving is the busiest; it is not."
The authorities in the western states were still grappling on Saturday with the aftermath of heavy rains and snow over the busiest travel weekend of the year.
Of the three children who were swept away in their vehicle in Arizona last Friday, officials initially the found body of the five-year-old about 4.8km downstream, said Gila County Sheriff Office's Lieutenant Virgil Dodd. The second of the three children turned up later on Saturday. The sheriff's office did not provide the age and gender of the second child or the third child who was still missing late on Saturday afternoon.
The agency said on Saturday that two other children and two adults who were in the vehicle were rescued from a small island and the bank of the creek in Tonto National Forest north-east of Phoenix. Sheriff's officials initially had said six people, including four children, were rescued last Friday at locations along the creek.
Families in California took advantage of the early season snow in the Grapevine area, sledding down slopes in Frazier Park, California. Traffic was heavy, but Interstate 5 was open in both directions as holiday travellers headed home.
High winds and ice were making travel almost impossible in some other places, however.
A 160km section of Interstate 80 in Nebraska and Wyoming closed on Saturday morning because of high winds and blowing snow. Several other roads and highways also were closed.
Back-to-back snowstorms and strong winds combined to seriously complicate travel by land across much of the rest of Wyoming, where roads were closed in the eastern and southern parts of the state because of whiteout conditions.
The National Weather Service in Wyoming reported 10cm of snow fell in Cheyenne from 7pm last Friday through 10am on Saturday "that has been blown all over kingdom come by our winds", said meteorologist Andrew Lyons.
That was added to 30cm of snow that fell before Thanksgiving.
Wind gusts up to 80kmh created ground blizzards and below-zero wind chill temperatures in some areas. A wind gust of 124kmh was reported in the mountains between Cheyenne and Laramie, Mr Lyons said.
All roads in and out of Casper were closed on Saturday morning, including the entire 483km of Interstate 25 in Wyoming.
Travel was also difficult in Colorado on Saturday, as winds blew around snow that fell in previous days.
North-eastern Colorado roads were closed due to strong winds, blowing and drifting snow and poor visibility.
In northern Montana, more than 30cm of fresh snow and strong wind gusts are expected to combine to create ground blizzard conditions along the Rocky Mountain front.
Meteorologist Christian Cassel told the Great Falls Tribune that people could be stuck in their homes for at least a day due to the near zero visibility.