The Boise hills are alive with green grass, and lots of it.
As temperatures warm, so will the 2019 fire season. Officials warn that the moist spring could lead to a delayed start with a more intense peak later in the fire season.
The period of Jan. 1 through May 31, 2019, is the wettest on record at the Boise Airport, according to the National Weather Service, with May 2019 being the wettest May since 2005 and the sixth-wettest on record overall.
“The cool, wet spring led to excess precipitation, allowing soil moisture to stay higher than normal with continued spring rain, so the grasses greened up robustly,” said Bryan Henry, acting fire weather program manager for predictive services for the National Interagency Fire Center.
The wet spring initiated grass growth at low and middle elevations, filling in patchy areas, increasing the fuel load and potentially prolonging the wildfire season.
“We have a healthy grass crop that is continuous. A lot of years it can be patchy, creating natural fire breaks. This year is different. Places that do not typically have grass do have grass,” Henry said.
A larger and more continuous fuel load could lead to a more active peak wildfire season with more fires and more large fires.
“We could have an above-average amount of fuel to burn and could potentially see a more active fire season along the Boise Front, and with added growth we have more fuel to burn. But it is all dependent on the weather,” said Chief Tony Piscopo, the division chief, wildfire, for the Boise Fire Department.
High winds, low humidity and high temperatures drive summer wildfires in the West. The wildfire season typically starts in June in Idaho, but the unusual spring has kept the start of the wildfire season at bay.
“Sometime around July 4 we could have our first multiday heat event of several days in the upper 90s, which is climatologically normal,” Henry said. “Heat will dry out grasses with 90- and 100-plus temps in later summer, and the first-of-July heat events could make those grass fuels dry enough to take fires.”
Piscopo encourages Idahoans not to be complacent this fire season.
“Use due diligence when recreating in the Foothills and remember that 85% of fires in the Boise Front are human caused, and this year it is more imperative to use extra caution,” Piscopo said.
“Make sure, when you tow boats or trailers, don’t drag chains or debris. When you have recreational fires, make sure embers will not start a fire, and be sure your fire is fully extinguished. Abide by fireworks regulations as we approach July 4.”
More fire prevention suggestions can be found at IdahoFirewise.org. Homeowners can take more precautions to mitigate their home for fire risks by making sure their home is fire adapted. The Ada Fire Adapted Community provides educational resources and more specific actions.
Rachel Hager is writing for the Idaho Statesman this summer on a fellowship through the American Association for the Advancement of Science. She is a master’s student in ecology at Utah State University and earned a bachelor’s degree in biology at Bryn Mawr College.