Willy Crippen uses a series of line graphs to gauge the wildfire danger, and the graph on his computer monitor Monday afternoon looked something like Mount Everest.
Crippen pointed the cursor at the point where one line, appropriately rendered in flame red, peaks.
That apex represents the highest level for potential fire growth that Crippen’s employer, the U.S. Forest Service, has measured for any July 30 during the period 1993 to 2015.
Monday’s measurement matched that peak.
Little wonder, then, that Crippen and fire managers from other agencies are anxious about a fire season that hasn’t even reached its most dangerous period, statistically speaking.
“We call it dirty August,” said Crippen, who’s the fire management officer for the Burnt-Powder Fire Zone, which covers most of the southern half of the Wallowa-Whitman National Forest. “Our peak of fire season historically is August 8, give or take a few days.”
So far a scarcity of lightning, which sparks a significant percentage of wildfires in the region most years, has made for a much quieter season in Northeastern Oregon compared with other parts of Oregon, California and Idaho.
But with a chance of thunderstorms today, Crippen was hardly complacent.
“We’re ramped up (for the potential for lightning),” he said. “The fires that have started elsewhere this year are really taking off, in California, Idaho. We haven’t had the starts, but the potential is definitely there.”
Fire danger higher than in 2015
The graphs that Crippen was examining in his Baker City office depict the “Energy Release Component” (ERC).
This index estimates the amount of heat a fire would produce, and it’s an effective way to gauge how difficult it might be to douse a blaze, Crippen said.
Northeastern Oregon is divided into six regions, each with its own ERC, updated daily.
On Monday the ERC for each of the six regions was either at or just below the record high for the date.
That’s worrisome in itself, but Crippen points out that the current ERCs are much higher than they were at this time in 2015 — less than two weeks before lightning ignited the biggest blaze in Baker County history, the 104,000-acre Cornet/Windy Ridge fire south of Baker City.
The current ERCs range from 79 to 84.
In late July of 2015, the average among the six regions was about 60, Crippen said.
The numbers have risen rapidly during July.
Early in the month the ERCs were close to average, Crippen said.
But July, with its nearly record-breaking heat and little or no rainfall, changed the situation substantially.
“Since July 25 or so we’ve been right on the maximum line (for the ERC),” Crippen said.
The fire threat is severe enough that the Forest Service and other agencies have been able to tap reserve budgets to bolster their firefighting forces.
Crippen said about 18 firefighters, some from Minnesota and others from Georgia, were slated to arrive early this week to work on the Wallowa-Whitman.
Steve Meyer, wildland fire supervisor at the Oregon Department of Forestry’s Baker City office, said the department is paying two private bulldozer owners $100 a day to be available if needed.
The Forestry Department also plans to hire two engines from local rural fire protection districts on a temporary basis, Meyer said.
“That’s convenient because they already know the country,” he said.
The Forestry Department has also contracted for two helicopters, one stationed in La Grande and the other in Wallowa County, to augment the region’s aerial firefighting fleet, Meyer said.
Calculating the fire danger
The process starts with a series of several remote, automated weather stations scattered about the region, Crippen said.
These stations collect temperature and humidity data which are used to estimate the amount of moisture in various types of fire fuels, ranging from grass to large logs lying on the ground.
The fuels are categorized by the approximate number of hours it takes for them to dry out after a wetting rain (at least one-tenth of an inch). Grass and twigs smaller than a quarter-inch in diameter, for instance, are known as “1-hour fuels” or “fine fuels.” The biggest logs, larger than 8 inches in diameter, are “10,000-hour fuels.”
(There are also 10-hour, 100-hour and 1,000-hour fuels.)
Fuel moisture is a crucial component in the equation used to derive the daily ERC, Crippen said.
See more in the Aug. 1, 2018, issue of the Baker City Herald.