Pacific storm systems will strike the Western US this weekend with heavy rain, mountain snow, and strong winds, according to US weather authorities.

The looming adverse weather comes as a separate system batters the eastern part of the country, with multiple casualties and travel chaos reported.

NWS Weather Forecast

US weather
(Photo : Photo by John Normile/Getty Images)

The National Weather Service (NWS) on Tuesday, December 27, stated a series of Pacific storm systems will affect the Western US with heavy rain, mountain snow, and strong winds into the upcoming weekend; where a stormy and unsettled weather will impact the region, as well as the Rocky Mountains.

With this, travel disruption in road traffic movement and commercial flights are possible.

Its short-range forecast also said there is an increasing shower and thunderstorm chances across parts of the southern Plains and lower Mississippi Valley by Thursday, December 29.

This is due to a developing storm system across the central and southern parts of the country, bringing increased threats of rain and some flooding concerns as the system moves east.

The NWS also updates previous forecasts of the expected warming of temperatures in the East Coast later this week, stating that well above average temperatures will surge into the central and eastern US from Wednesday, December 28, or later this week.

Also Read: Widespread Snowfall Unloaded in Portions of Northern Ireland and Scotland

American West Active Weather

The US weather agency adds most of the active weather in the next few days is anticipated to be focused around the western half of the US as a weather pattern change brings in rain and mountain snow across the region.

This comes while the central and eastern US experiences a rapid warm up.

For instance, a deep and fast-moving storm system hovering through the Intermountain West on Tuesday evening is expected to continue producing substantial localized heavy rain across the West Coast and parts of central and southern California by early Wednesday.

Scattered flash floods are also possible with increased chances for rapid runoff and debris flow near recent burnt scars, the agency says.

Moreover, heavy snow is possible across the high-altitude terrain of the Sierra Nevada, Cascades, and Rockies as moisture flows eastward along a potent Pacific jet streak.

Potent Atmospheric River

In relation to the Pacific storm systems, a potent atmospheric river is causing heavy coastal rain and mountain snow across the Western US, with all 11 Western states expecting to receive further rain or snow, with the heaviest projected impact for California, according to CNN.

By Tuesday evening, the said weather hazards had knocked out electricity to about 140,000 customers in Oregon, 18,000 customers, in California, and 31,000 in the state of Washington, according to utility monitoring site PowerOutage.US.

As described by US weather authorities, an atmospheric river a long, narrow region in the atmosphere or river in the sky that can carry and transport moisture for thousands of miles.

It is also the reason why flood watches were issued by the authorities for over 5.3 million people across most of the West Coast, including Seattle, as reported by the US news network.

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