US weather: 'Parade' of SEVEN storms to trigger Christmas chaos as 'brutal' snow and rain plough across America

‘Brutally’ cold air from the north will collide with milder southerly gusts to drive volatile atmospheric instability.

Holidaymakers are warned to prepare for ‘multiple rounds’ of snow, and wintry weather which threaten roads and airports.

AccuWeather long-range expert Joe Lundberg said: “We’re expecting some wintry weather across pockets of the Northeast and a parade of storms across the Northwest for the holidays.

“There could be as many as seven different storms impacting the Northwest through next weekend.

“The mountain snow could cause travel troubles, but it will be great for skiers and snowboards.”

He said ‘brutally cold weekend weather’ will bolster a separate ‘Alberta clipper’ storm due to hit the mid-west and Great Lakes.

The fast-moving storms which come out of Canada are known for triggering quick eruptions of severe weather.

An atmospheric river of moisture from the Pacific will drive multiple storms into the west coast through the run-up to Christmas.

California, Washington and surrounding north-western states are braced for snow and heavy rain.

AccuWeather meteorologist Bernie Rayno said: “A parade of storms are expected to bring snow, rain, ice and a wintry mix to parts of the Northwest, as well as Northern and Central California.

“Snow showers and a wintry mix could impact parts of the Northeast and lower Great Lakes on Christmas Eve.

“Rain and showers are expected across parts of the Ohio Valley, Mississippi Valley and Gulf Coast, as well as eastern Florida, on Christmas Eve.”

People travelling for Christmas are warned to take extra care as swaths of the country are gripped by ‘nasty weather’.

And as temperatures plunge on the east coast, the west will be milder than typical for winter.

Weather Channel meteorologist Jonathan Belles said: “Christmas or Hanukkah travel is ahead for millions, and the weather will definitely need to be a factor before hitting the road because for some, snow and nasty weather could disrupt plans.

“Much of the west coast will see several days of rain or snow while parts of the South, Midwest and Northeast could be affected by a system early in the week.

“Temperatures will be mild and warming for most of the country leading up to the holidays.”

Jim Dale, US meteorologist for British Weather Services and co-author of ‘Surviving Extreme Weather’, said: “There will be an ongoing risk of storms through the holiday, with little chance of snow over Christmas.

“It will be very mild to the northwest, however a Pacific train or atmospheric river will bring unsettled weather through the period.

“Where cold and warm air collide, storms will be a risk through the end of the year.”

The US National Weather Service has winter weather advisories in force across northern states, with separate ‘freeze’ and wind warnings further south and east.

A spokesman said: “The heaviest precipitation is expected in and near northern

"California Monday night and Tuesday, which carries some risk of excessive rainfall and flash flooding.

“Cold Weather Advisories are in effect across portions of eastern Upstate New York and northeast Pennsylvania, while freeze warnings and frost advisories are out for portions of southeast Georgia and North Florida.”