February wave of cold and snow, breaking records in some places, gave the water
supply outlook a striking boost through much of the Columbia Basin, but all
places were not equal.
a result, the April-September forecast has not changed significantly for flows
at The Dalles Dam, the final chokepoint for basin-wide runoff, said Ryan Lucas
of the Northwest River Forecast Center in Portland during a teleconference on
Lucas pointed out how basin-wide fortunes have changed since the end of
January, when lagging snowpack, warmer-than-average temperatures and
below-average precipitation prevailed.
can see in the Upper Columbia, it was much colder than it was during the first
months of winter … The southern two thirds of our basin really saw some
significant precipitation, with records set in some places,” Lucas said.
the basin is “looking closer-to-normal or above-normal precipitation,” he
added, specifically citing central and southern Oregon’s previously parched
Cascade range, and the entire Snake River Basin.
River basins now have April-September water supply forecasts ranging from 66 to
140 percent of average, while Columbia River Basins above Grand Coulee Dam have
forecasts of 79 to 107 percent of average and the west side of the Cascades are
at 81 to 94 percent of average.
this represents a big turnaround from conditions that were present at the end
of January, Lucas said. However, extremely cold temperatures produced a lot of
light snow with less snow water equivalents in some areas.
through September water supplies as of March 6, compared to Feb. 5 on a 30-year
average, break down like this:
Columbia River at Grand Coulee Dam are at 87 percent compared to 89 percent;
Upper Snake River basins are at 103 percent compared to 84 percent; Middle
Snake Tributaries are at 103 percent compared to 67 percent.
resulting balance for the Columbia River at The Dalles Dam is 87 percent of
average as of March 6, compared to 87 percent as of Feb. 5.
April-Sept. water supply forecasts for the west Cascades are lowest from the
northernmost on the Skagit River near Concrete at 84 percent of average to the
highest at the southernmost Rogue River, which as at 113 percent of average.
swings throughout the basin over the last month have been striking. Temperature
departures in the Columbia Basin above The Dalles averaged out at nearly 10
degrees below normal. That’s compared to a departure of 4 degrees above normal
at the end of January.
said there has been significant cold and snow at lower elevations, which can be
more difficult to monitor aside from established weather stations in towns and
cities. Record cold and snow were recorded for February in many of those
Bend, Ore., received nearly 46 inches
of snow in February, almost doubling a record that has stood for more than a
century. It was also the third coldest February on record for Bend.
Coeur d’ Alene,
Idaho, experienced the longest cold spell on record, punctuated by a low of
minus 2 degrees — the first below-zero temperature dating back to December of
2016. As of early this week, the city had received just over 56 inches of snow,
and any snowfall that would exceed 57.8 inches over the next few weeks would
exceed a February-March record for snowfall set in 1955.
The National Weather
Service in Missoula reported that February was the snowiest ever in Kalispell,
Mont., with just over 33 inches recorded. And, it was the second coldest
February on record for Kalispell, with an average 12.6 degrees. The record of
4.9 degrees was set in 1936.
And Seattle marked
its year of “Snowmaggedon,” the snowiest winter in 50 years as of the end of
February, with 20.2 inches, shattering the record of 13.1 inches set in 1949.
February of 2019 was also the third coldest on record for Seattle with an
average temperature of 36.7 degrees.