US snow warning: Thundersnow deluge to blanket America under a FOOT of snow

Cold air sweeping the Rockies, and High Plains, Colorado and New Mexico through the coming days will dump between six to 12 inches of snow.

The Great Lakes and Lake Ontario are also in the firing line with heavy snow forecast from mid-week up to the weekend.

Temperatures will nosedive 25F below average for the time of year with the chilly bite reaching as far south as Florida.

A spokesman for the US Weather Service (NOAA) said: “A powerful system will bring winter impacts to southern and eastern Alaska.

“A cold front moving across the Upper Great Lakes will produce light to moderate lake effect snow, with the highest totals expected across Lake Ontario.

“An area of low pressure is expected to develop and produce moderate to heavy snow across portions of the Southern Rockies and High Plains, and between six and twelve inches of snow are possible over portions of southern Colorado and northern New Mexico.”

Snow will be heaviest over high ground, although it will settle to lower regions through the coming days, he said.

Warm air laden with moisture will clash with the cold plunge to trigger thunderstorms, he added.

He said: “There's still some uncertainty with the track of this system and snow levels, with some accumulating snow possible as low as 5,500 feet and as high as 7,500 feet.

“Showers and thunderstorms are expected over western Texas where warm moist southerly flow gets into the region.”

A cyclonic low-pressure system will push a belt of cold air over the Rockies and Colorado, reaching as far south as Texas.

Temperatures will ‘rollercoaster’ from unusually mild to much colder than average for the time of year.

However, thermometers are set to rise again in the run up to the Festive season, according to The Weather Channel.

Meteorologist Kait Parker said: “Changes are in store for temperatures across the country, and a lot of that is thanks to this low this low that's going to exit the Rockies and bring cold air not just across Colorado but into the desert southwest and Texas.

“The panhandle of Texas going to be much colder over the next couple of days and we are also going to see a big change in temperatures across the northern tier.

“But those temperatures are going to be changing once again very quickly; it is that time of year that we see big changes afoot although in general the trend is warmth over the next couple of weeks.”

Although the mercury will rise through the second half of December, Christmas snow is now possible.

Jim Dale, US weather correspondent and meteorologist for British Weather Services, said: “It is going to feel very seasonal over the festive period.

“There is likely to be snow in the run up to Christmas and during Christmas week, particularly around the Great Lakes.

“But it is then a race to see if it hangs around for Christmas Day.”