This snowstorm ‘unusual,’ on its way out of the Treasure Valley

The Treasure Valley’s Christmas storm is almost over, according to National Weather Service meteorologists, but it dropped an unusual amount of snow as it passed through on Friday and Saturday.

Meteorologist Jay Breidenbach said the storm dropped a total 7.2 inches of snow, leaving just over 9 inches on the ground at the Boise Airport thanks to previous accumulation. Earlier in the day, there was a boost of 1.3 inches in just three hours, as NWS Boise tweeted a snow total of 5.8 inches around 6:30 a.m.

NWS meteorologist Joel Tannenholz said it’s “really not that common to get this much snow,” despite late December being prime storm season for the Treasure Valley.

As of Dec. 24, the month’s snow total was 10.2 inches — the greatest since December 2008, when totals hit 20.2 inches. The past few years have seen only 2-5 inches for the entire month, Tannenholz said.

In 2008, multiple storms throughout the month led to such a high snow total, where current conditions have been caused mostly by this weekend’s storm. That has helped 2016 surpass the maximum snow depth from 2008, when the most snow on the ground at once was only 7 inches, thanks to higher temperatures and spread-out snowfall.

Later in the day on Christmas Eve, the storm was heading due east, said Tannenholz, and was tapering off in the Boise area.

But that’s not the end of the wintry weather for the Treasure Valley. Another storm will roll in on Monday and Tuesday, Tannenholz said, though that will move through more quickly.

Temperatures aren’t expected to rise above freezing over the next week, he said, which means all the snow and slush on the ground is not going anywhere.

“We’re not going to see freezing for a long time,” Tannenholz said.

He said the rest of the month is expected to see lower than normal temperatures and about average precipitation.

Travel and road conditions

The accumulating snow and low temperatures this weekend have led to messy roads that had caused seven crashes and 12 slideoffs between midnight and 9:30 a.m. Saturday, according to an Ada County dispatcher. None of those involved injuries, the dispatcher said.

According to 511, there were no critical traffic incidents statewide, though Interstate 84 and several highways in the Boise area showed patches of ice and packed snow on the roadway, according to a recorded message.

Ada County Highway District traffic cameras showed many roads with slow or stop-and-go traffic.

Idaho State Police on Saturday sent out a release asking people to use caution when driving, slow down and increase following distance.

“In the last two weeks, the Idaho State Police have had five patrol cars hit while on the interstate performing investigations,” the release said. “Canyon County Sheriff’s Office has had three patrol cars hit in the same time period.”

The agency said it has responded to over 230 crashes this month, in addition to the incidents handled by other local agencies.

Local law enforcement on Twitter encouraged people to drive carefully and stay off of the roads if possible.

Though the Boise Airport remained open Saturday morning, at least six flights had encountered delays around 10:30 a.m., while one Delta flight to Seattle was canceled entirely, according to an online flight tracker.

Nicole Blanchard: 208-377-6410, @NMBlanchard

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