White Christmas happening now in Olympia and there’s hope for Tacoma

UPDATE 3:45 p.m.: Emergency vehicles are on state Route 512 at Steele Street. First responders are being dispatched to numerous other vehicle collisions in the region.

UPDATE 3:30 p.m.: Radar is showing light snow falling from Seattle to Olympia with snow turning to rain on the coast.

A White Christmas has hit Olympia Sunday afternoon and there’s hope for Tacoma.

First, what exactly is a White Christmas?

NOAA’s National Centers for Environmental Information has an official definition for White Christmas: One inch or more of snow at 7 a.m. on Christmas Day.

Children all over the U.S. use a different definition, one that can be roughly summed up as, “There’s a Christmas tree in my house and it’s snowing outside.”

The National Weather Service in Seattle and scores of Twitter users have been reporting snow falling from Chehalis to Olympia Sunday.

As of 3 p.m. the snow was reaching Joint Base Lewis-McChord.

The Weather Service was predicting up to two inches of snow in the hardest hit areas through 10 p.m. Sunday night. They acknowledged that the region’s temperatures teeter on the snow-rain border.

“The air mass is borderline cold enough for snow,” the Weather Service said in a statement. “Small changes in the forecast variables can result in a major change in the snow forecast.”

Craig Sailor: 253-597-8541, @crsailor