TRUCKEE - Early summer showers slowed the start of the fire season, but ongoing drought conditions are expected to make the next six months long ones for Western firefighters, according to a fire prediction released this week.
The prediction is particularly bleak for the Sierra Nevada.
"Huge fires are indeed projected for much of northern California and the Sierra Nevada range," said Ron Neilson, a botany professor at Oregon State University and bioclimatologist with the U.S. Forest Service's Pacific Northwest Research Station, in a statement.
How those predicted fires get started is the big unknown.
The prevalence of thunderstorms is key when predicting wildfires, and one that is difficult for scientists to foresee, Neilson said. The National Weather Service in Reno predicts slight chances of thunderstorms in the region throughout the weekend.
"It's usually lightning storms that trigger multiple fires," Neilson said. "Our computer models are pretty accurate at determining the vegetation, moisture and climatic conditions that set the stage for fire, but can't always predict whether or not something will actually light them."
Part of what's interesting about this year, Neilson said, is that it appears an El Nino is beginning and there may even be tentative shifts in the Pacific Decadal Oscillation. Both El Nino and the Pacific Decadal Oscillation are large climatic forces that can affect weather on broad regional or global scales, Neilson said.
The concern is that an evolving El Nino, reinforced by a changing Pacific Decadal Oscillation, could be exactly the type of conditions that set the stage for the broad, turbulent storms that can produce a lot of lightning, Neilson said.
"Lately we've had unusually turbulent weather in the U.S. for the summer months," Neilson said. "The Midwest is getting heavier-than-normal rain, and we've had some very unusual and powerful storms in the West as well. Everywhere I go, people keep saying the weather is just really, really weird."