What a difference one winter can make: Fire season this year is predicted to be less active than last year’s, because of wetter than average weather and a beefy snowpack.
“We’ve got a lot of snow to melt,” Tim Mathewson, fire weather program manager for the Bureau of Land Management, said Thursday, in addressing the West Region Wildfire Council by phone.
The predicted El Niño weather pattern (generally characterized as warming water in the Pacific), along with snowpack that sits about 133 percent of average for the year — compared with an anemic 69 percent of average for this time in 2018 — puts April - July at below-average fire risk in many elevations.
Extra moisture also means more grasses and fuel, which “could be a player later on,” Mathewson cautioned. Although more fires might start, there are not necessarily going to be more large fires, as were seen in the state last year, he said.
Last season, La Niña weather patterns brought dry conditions to the desert Southwest, which put firefighting agencies on immediate notice as soon as February.
“The writing was on the wall very early,” Mathewson said. The dry conditions and slim snowpack meant fuels that should have been under snow, taking on moisture, weren’t; in fact, the snow-water equivalent for early 2018 was the third lowest measured since 1992.
“That’s changed. Right now, we’re tied for the second-highest snow-water equivalent,” Mathewson said.
The forecasted El Niño weather pattern bodes well for the 2019 fire season, although there are always variables, he said.
“We’ve been able to recognize some of these pre-season conditions leading into our warm season a lot better than we used to and snowpack obviously is one of them. But this time of year is also very important,” Mathewson said.
“Above-average snowpack in winter does not necessarily remove the threat for a big fire season. Spring months are very important. March, April, May, we really start focusing in, not only on snowpack, but weather patterns, trends — everything. This is really the time of year to sink our teeth into those kinds of predictors, not necessarily what’s happening in December.”
Fire forecasters consider likely moisture conditions for the three spring months. “Does the wet season look wet? So far, yes. It has,” Mathewson said.
Forecasters also look at June and July’s “pre-monsoon window,” the period when snow melts in higher elevation and grass begins to dry out.
“We start to see an increase in fire activity during that time. It’s always a race against the dry period and when the onset of the monsoon is. That’s really what we’re focused in on — does it come early; does it come late?”
A dry spring means early onset for fire season and also increases the monsoon window.
Above-average snowpack tends to mean a less busy fire season. “We still have fires. I tell people, even big snowpack years do not eliminate large fire activity. But it does reduce the severity and it tends to reduce how long fire seasons are,” Mathewson said.
It is not unheard of to have grass fires start in spring, but that does not mean fire season itself has come early, he added. Grass fires are usually human-caused, not lightning-sparked.
“There’s definitely been a significant improvement, especially across Colorado from this time last year. Cooler than average temps have held onto the snowpack that we’ve had that’s above average,” he said.
Alan Staehle of the Ouray Fire District said last winter, significant dust blew in, accelerating snowmelt and bringing early spring runoff.
But this year, fewer significant wind events and more moisture are expected, reducing that possibility, Mathewson said.
He later asked council members for their take on fuel-loading.
“We’re just kind of holding our breath, waiting to see. We definitely expect the grass to be high,” Joe Conway, Norwood Fire’s chief, said.
Mathewson said more snowpack raises the possibility of flooding rivers as runoff begins. The cooler weather may delay the start of monsoon season, which could mean the increased fuel load will have more time to dry out.
“I don’t think it necessarily puts us into an above-average (fire) regime as we get into late June and July. We have to melt a lot of snow between now and then to really get into that and we have a green-up to go through. The heavy fuels that are on the ground are going to take on a lot of moisture,” Mathewson said.
“The wildcard every year is beetle-kill (trees),” he added. The trees destroyed by insect activity provide ready fuel for ground fires; the West will continue to deal with the effects from the beetles for years to come.
“Overall, we’re definitely sitting different than we were last year,” with fire risk “nowhere close” to being as severe as it was in 2018, Mathewson said.
Katharhynn Heidelberg is the senior writer for the Montrose Daily Press. Follow her on Twitter @kathMDP.