Second storm system rolling in

While last weekend’s predicted snowstorm largely bypassed the Spokane and Coeur d’Alene areas, forecasters Tuesday said the region could get heavy snow today and Thursday.

A low-pressure system moving south out of northern Canada was expected to bring varying amounts of snow. Spokane could see 2 to 6 inches, said John Livingston, the meteorologist in charge of the National Weather Service in Spokane.

A winter storm watch was upgraded to a winter storm warning Tuesday for much of the Inland Northwest, including Spokane, Stevens, Pend Oreille and Whitman counties; all of North Idaho; and northwestern Montana.

Highs for today are forecast in the teens in Spokane.

The storm warning for today and Thursday called for 4 to 7 inches of snow in valley areas and 8 to 14 inches in the mountains.

Livingston said predicting snowfall amounts has been difficult because both Friday’s and today’s expected storms were formed by an unusual combination of frigid northerly air and moisture off the Pacific coast.

“The flow is pointed right at us from the north,” he said.

The storm Friday made an unexpected, last-minute change in direction, weather service meteorologists said.

Forecasters had called for as much as a foot of snow, but by Saturday morning, only light snow had fallen in Spokane and Coeur d’Alene. Heavier snow – 4 to 8 inches – came in a hit-and-miss pattern to locations such as Wenatchee, Waterville, Pullman, St. John and northern Pend Oreille County.

Forecasters correctly predicted the arctic cold that sent the thermometer to minus 5 degrees in Spokane early Tuesday with colder temperatures in outlying areas.

On Tuesday, the low-pressure system originating over the Arctic Ocean was headed south. The system was expected to strengthen is it moved down the British Columbia coast, drawing enough ocean moisture to cause moderate to heavy snow.

Forecasts called for dry snow, with an average 20-to-1 ratio of snow to melted precipitation. Such dry snow is normally easier to shovel and maneuver across.

Another shot of arctic air is expected by Friday. Lows will likely drop below zero Friday and Saturday nights before rebounding slightly Sunday. Highs Saturday are forecast at 3 to 6 degrees.