OREGON STATE UNIVERSITY

Welcome to spring – when snow isn’t as unusual as you might think…

03/21/2012

CORVALLIS, Ore. – Many Oregonians woke up Wednesday morning to a blanket of snow, slushy roads and the realization that the arrival of spring doesn’t necessarily mean it’s time to get out the sunscreen.

But such weather isn’t all that unusual in western Oregon – especially during a La Niña winter, according to Kathie Dello, deputy director of the Oregon Climate Service at Oregon State University.

“This is the La Niña winter weather we’ve been waiting for,” Dello said. “It’s pretty typical – an active storm track, wet and cool. It’s a bit later than we’ve expected, but low-elevation snow in March isn’t unprecedented.

“La Niña is officially waning,” Dello added, “but she’s still got some fight in her.”

Late-season snow can be particularly problematic, Dello said, because it typically is wet and heavy, putting trees, branches and power lines in peril. Yet the cold, wet weather brings positive attributes along with the negative. Oregon’s snowpack is starting to recover and southern Oregon, in particularly, needed more snow in the mountains.

Despite the flooding in mid-January, the period from December to February was drier than normal. “It was the 10th driest winter on record in Oregon,” said Dello, who is in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

Weather in the Pacific Northwest is in sharp contrast with much of the rest of the country, Dello noted, which is experiencing record high temperatures.

Just how unusual is spring snow? Dello says a quick check of the record books shows that March can indeed go out like a lion – and that April showers aren’t always rain. The year 1951 was particularly cold and wet, with up to eight days of measurable snowfall in much of western Oregon.

  • Corvallis: The latest measurable snowfall came in 2008, when 0.3 inches fell – believe it or not – on April 20. The heaviest March snowfall took place in 1960, when four inches fell on March 3.
  • Portland: The year 1951 was memorable in the Rose City, which had eight days with measurable snowfall in March of that year at the Portland Airport. The deepest March snowfall was on March 8, 1951, when 7.6 inches fell. Portland’s latest snowfall was on March 25, 1965, with 0.3 inches.
  • Eugene: There were five days of measurable snowfall in March of 1951 in Eugene, led by 4.9 inches on March 5. The latest snowfall was 0.5 inches on March 25, although snow records are spotty and snow was reported on April 20, 2008, but not recorded at the airport station.
  • Salem: There were eight days of measurable snowfall in 1951, but the highest March snowfall in Salem was on March 2, 1960, when 6.7 inches fell. The latest snowfall was 0.1 inches on April 8, 1972.

“Historic snow records can be a bit spotty,” Dello said, “and in some places, the overnight snowfall might be at near-record levels. There also is a lot of local variation. We’ve had volunteer observers with the CoCoRaHS program measure more than six inches of snow outside of Eugene today, and 4.5 inches in Monroe of southern Benton County.”

The program – known as the Community Collaborative Rain, Hail and Snow Network – helps experts enhance their snow observations by measuring and reporting local levels. More information on the program is available at: http://www.cocorahs.org/Maps/ViewMap.aspx?state=usa

Dello frequently provides weather facts and historical data via Twitter at: www.twitter.com/orclimatesvc