Temperature difference from normal across Lower 48 at 7 a.m. ET December 31 as simulated by GFS model (WeatherBell.com)

Winter has taken control of the Lower 48 to close out 2014.  Much of the nation is experiencing colder than normal temperatures and a rare snowstorm is sweeping across the Southwest. In Las Vegas, snow has officially been reported.

Southwest snow

Snow and high winds sweeping through southern California’s San Bernardino mountains early Wednesday stranded more than 100 motorists, writes USA Today:

The San Bernardino County Fire Department said in a news release that 136 people were rescued on State Highway 138 near the communities of Crestline and Mount Baldy, about 50 miles from Los Angeles.

The snow level dropped to about 1,000 feet and 6-12 inches or more fell in a number of area.  Watch this video taken near Wildomar, CA, which is just about an hour from Los Angeles:

Here are few photos of the snow in Southern California:

Snow has also fallen in portions of Arizona unaccustomed to it:

And yes, snow in Las Vegas!

A winter weather advisory is in effect through this afternoon in Sin City, for generally trace amounts of snow.

The snow comes courtesy of an intense upper level low pressure system cycling across the Southwest, being fed by the frigid cold air mass to the north and northeast.

Simulation of upper level low pressure system over Southwest U.S. from NAM model (WeatherBell.com)

Cold weather over Lower 48

With the exception of Florida, the entire Lower 48 is experiencing colder than normal temperatures today.

In some areas, temperatures are downright frigid. Laramie, Wyoming dipped to 30 degrees below zero this morning.

Look at some of the wind chills (or “feels like” temperatures) in the northern Rockies and Northern Plains this morning:

The average morning temperature across the Lower 48 was just 14 degrees, notes WeatherBell Analytics meteorologist Ryan Maue:

Maue notes it was the coldest December morning for the lower 48 in 16 years, since December 23, 1998.

Those planning to celebrate the New Year in the Florida, where temperatures are warmer than normal, must be soaking it up. Meteorologist Paul Douglas, who writes a weather blog for the Minneapolis Star Tribune, says the temperature difference between the Twin Cities and Orlando will be about 100 degrees later this week.