OREGON STATE UNIVERSITY

November snow rare, but not a record…

11/22/2010

CORVALLIS, Ore. – Snow in the Willamette Valley before Thanksgiving? It is unusual, though not unprecedented, say researchers at Oregon State University.

One of the earliest snowfalls on record at Hyslop Farm near Corvallis was in 1955, when 1.5 inches of snow fell on Nov. 12, according to Kathie Dello of the Oregon Climate Service at OSU.

This week, she says, is a classic case for valley snowfall.

“When you have a storm system that mixes with cold, Arctic air you can get snow,” Dello said. “But it may be premature to say that this is a result of a La Niña winter. What we can say is that these types of events are more likely to happen when there is a La Niña.”

The winter of 1955-56 was a snowy one, Dello pointed out, with 15.8 inches of snow overall in Corvallis. In fact, after that Nov. 12 snowfall, the valley was pelted again four days later with 3.5 inches, and an additional 4.5 inches the next day.

Corvallis has one of the most accurate long-term weather stations in the state, with records going back to the late 19th century. That’s why Dello can tell you that another early snow event took place in 1896, when two inches of the white stuff fell on Nov. 16.

“Unfortunately,” she said, “snowfall records throughout the state have been historically spotty, so it’s difficult to compare events over the years.”

Among the earliest snowfalls in Corvallis history:

  • Nov. 12, 1955 (1.5 inches)
  • Nov. 16, 1955 (3.5 inches)
  • Nov. 16, 1896 (2.0 inches)
  • Nov. 17, 1955 (4.5 inches)
  • Nov. 20, 1896 (0.5 inches)
  • Nov. 20, 1978 (1.0 inches)
  • Nov. 22, 1977 (3.3 inches)
  • Nov. 30, 1967 (0.3 inches)
  • Nov. 30, 1985 (0.3 inches)

The Oregon Climate Service, affiliated with OSU’s College of Oceanic and Atmospheric Sciences, is the state repository for weather and climate information.