Fire season shaping up to be a slow one

Sean C. Morgan

Fire season isn’t shaping up to be a big deal in the area this summer, but, as always, that forecast comes with a caveat.

“Late start, a little below average, based on long-term weather forecasts and the snowpack,” said Unit Forester Ed Keith, Oregon Department of Forestry Sweet Home Unit.

That is unless a big lightning storm hits, which is hard to predict.

Rainfall at the Sweet Home Unit is roughly 140 percent of average at this point in the year, Keith said. The rain gauge shows 28.7 inches of precipitation so far this year.

The May 1 Oregon snowpack was approximately 187 percent above normal, and snow melt dates are projected to be three weeks to a month later than usual this year. This will be the fourth year in a row the snow melt was later than usual.

According to the ODF’s 2011 Fire Season Outlook, winter weather conditions were strongly influenced by La Niña conditions, cool sea surface temperature anomalies in the tropical Pacific Ocean, the strongest since 1974 and 1976.

Cool ocean temperatures on the Pacific indicate a shift to cold phase of the Pacific Decadal Oscillation cycle, according to the ODF forecast. Warm and cold phases alternate on a 30-year cycle. The warm phase lasted from 1977 to 2007, and the current cold phase is expected to last through 2036, producing colder, wetter winters and milder fire seasons in the Pacific Northwest.

Severe fire seasons in Oregon and Washington are five times more likely during the warm phase of the PDO, based on Forest Service annual acres burned, according to the report.

Based on weather patterns and past years that match them, the ODF is anticipating that July and August will be cooler and wetter than usual.

The report also forecasts one to three lightning episodes, with the earliest in late July. Normally, there are three to four lightning episodes, which are defined as 149 fires or more in a three-day period. Most of the lightning is predicted to be wet.

Prevailing onshore flow will result in periodic light rain and cool temperatures in western Oregon and Washington.

The number of marine push events along the east slopes of the Cascades and the Columbia Basin will be higher than normal.

Other than a few grass fires in July, the worst of the fire season will be limited to a few weeks in August and early September, according to the report. The exception will be in the Columbia Basin and eastern slopes in Washington and northern Oregon, which should have an average fire season.

The Sweet Home Unit will start the year with full crews on June 13, Keith said. They’ll be trained and ready by July 3.

The annual multi-agency fire school is scheduled for the week of June 20 in Sweet Home.

Last year, crews had a late start due to state budget cuts, he said. With some funds left over at the end of the fiscal year on June 30, the agency will be able to fund the crews on time for this fire season.

Fire officials from Linn and Benton counties will meet May 26 to discuss the upcoming fire season and the annual burn ban, said Forest Protection Supervisor Chad Calderwood. June 15 is the typical start of the burn ban.

“Our greenup is going to last a little longer,” he said.

That vegetation becomes fuel when it dries during the summer. More fuels can mean more fires, but the wetter weather getting there works against the fire threat.

Lightning activity is the key, Keith said. “It’s always going to be dry late August through early September.”