CORVALLIS - If you heard a little more grousing than usual about the wet weather this spring, it was for a good reason. Much of Oregon experienced the wettest May in the state's recorded history.
The cause may have been the lingering effects of one of the strongest El Nino events of the century. Whatever the reason, it turned normal weather patterns on their ear, said George Taylor, a faculty member in Oregon State University's College of Oceanic and Atmospheric Sciences and the state climatologist.
"A series of storms hit northern California and wrapped around the Cascades into eastern Oregon," Taylor said. "They would circulate around the east side of the Cascades, then swing over to the west side. The coast wasn't as affected. It was completely backwards from what we normally get."
As a result, many stations east of the Cascades set records. In Sisters, for example, the average May precipitation is 0.59 inches. The record, set in 1993, was 2.88 inches. This May, the station there recorded 3.95 inches, a whopping 669 percent of normal.
Antelope, with 5.57 inches, received five times its normal precipitation and shattered the old record of 3.64 inches set in 1977.
And Huntington, with 5.23 inches, nearly doubled its old record of 2.63 inches set in 1991. Normal precipitation there in May is less than an inch.
"There were a lot of sites in eastern and central Oregon that had 500 percent or more of their normal rainfall," Taylor said.
The west side of the Cascades didn't escape the persistent rain, either, Taylor pointed out.
Roseburg recorded 6.33 inches, breaking the 1996 mark of 4.45 inches, and easily eclipsing the normal level, a mere 1.52 inches.
Coquille had 7.21 inches, well above its normal 2.65 inches. That broke the old mark of 5.79 inches set back in 1911.
Portland had 5.55 inches, breaking the record of 4.88; Salem also had 5.55 inches, topping its previous mark of 4.61 inches. Both sites normally get around two inches in May.
Corvallis, with 5.80 inches, only broke its old record by about a tenth of an inch. But the record had stood for more than a hundred years.
The good news, Taylor said, is that the pattern likely won't continue.
"As soon as June hit, we got warmer and drier in a hurry," he said. "There may be a little rain now, but we will continue to move into gradually warmer and drier weather as the summer progresses."
The Oregon Climate Service, headquartered at OSU, has detailed information on a variety of weather-related topics. More information is available through its web site:Note to Editors: This story originally contained a World Wide Web address. The characters used in Web addresses will not telecommunicate in our system. Please call us at 541-737-0801 for the address.
A sample of May precipitation records:
STATION/MAY 1998/NORMAL/OLD RECORD-YEAR
Antelope/5.57 inches/1.11 inches/3.64 inches, 1977
Bend/4.11 inches/0.88 inches/3.76 inches, 1945
Coquille/7.21 inches/2.65 inches/5.79 inches, 1911
Corvallis/5.80 inches/1.95 inches/5.71 inches, 1896
Huntington/5.23 inches/0.93 inches/2.63 inches, 1991
Leaburg/8.56 inches/3.72 inches/8.16 inches, 1960
Portland/5.55 inches/2.06 inches/4.88 inches, 1996
Roseburg/6.33 inches/1.52 inches/4.45 inches, 1996
Salem/5.55 inches/1.88 inches/4.61 inches, 1933
Sisters/3.95 inches/0.59 inches/2.88 inches, 1993
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George Taylor, 541-737-5705