When the National Weather Service issued an excessive heat warning early this week for much of Washington’s eastern half, it was no surprise.
High heat had been baking the region and no notable rain had fallen for more than a month.
Even before the warning went into effect on Sunday, conditions were hot and bone-dry enough that a burning truck along Interstate 90 west of Cle Elum sparked a nearby brush fire. The blaze spread quickly, burning 8 acres before firefighters could contain it.
Two days earlier, a wildfire west of Chelan prompted home evacuations and forced the closure of a stretch of U.S.-97.
Now, as temperatures descend into the low-to-mid-80s, it feels like a celebratory cool-down. Even so, a volatile fire season continues to unfurl in Washington and other Western states.
“Fire danger is climbing,” warned the National Interagency Fire Center based in Boise. Warmer-than-normal temperatures and little rainfall, combined with dried-out trees, grass and other foliage and the increased possibility of lightning strikes, will produce “above average to extreme wildfire activity” through August and into September, the agency stated.
Washington, California and other states thought they had dodged a bullet last summer until a swarm of wildfires erupted starting in mid-July. Dozens of large blazes raged across our state, prompting Gov. Jay Inslee to declare a state of emergency so the National Guard could help fight the fires. By early September, air quality alerts were issued as smoke shrouded our skies and the air smelled of burned wood. Ash fell in Seattle.
But the worst fire season in state history was in 2015, when more than a million acres burned June through September. In central Washington, entire towns were evacuated, hundreds of homes were destroyed and three firefighters were killed. The Okanogan Complex of wildfires became Washington’s largest ever recorded, beating the record set just a year before with the Carlton fire that burned in the same county.
Obviously, no one can predict what will happen as August unfolds, but some similar conditions exist to those in 2015 and 2017. In a nutshell, an extended period of warm, dry weather has left a rich carpet of brush, grass and other vegetation ripe for ignition by lightning strikes and sparks by humans.
May was Washington’s second warmest May on record. Temperatures statewide ran several degrees above average in June and July. The last meaningful rainfall in the Inland Northwest was on June 21.
As we emerge from the caldron of upper 90s and triple-digit temperatures this week, may slightly cooler weather give us – and the hard-working wildfire crews – some relief.
Nic Loyd is a meteorologist with Washington State University’s AgWeatherNet. Linda Weiford is a WSU news writer and weather geek. Contact: email@example.com or firstname.lastname@example.org.