Comment A quiet end of summer for wildfires in the West may come to an abrupt end. Weather models indicate a potentially extreme and prolonged heat wave will develop across western states this week and into the Labor Day weekend. The National Weather Service in Sacramento is warning of a “very dangerous heat hazard” with high temperatures well above 100 degrees. Although a supercharged monsoon has brought a welcome respite from the smoky summer skies and devastating wildfires of the past two years, not all areas have seen drenching rain. Much of California enters the fall parched and flammable after a months-long dry spell, as do parts of the Pacific Northwest in Nevada, Idaho and Montana. And the heat wave arrives just as stormy weather conditions begin to increase in the West. “Because of the last two-plus years of drought, the fuels are ready to go and it’s just a matter of getting things in line in terms of weather and ignitions,” said Alex Tardy, warning coordination meteorologist with the National Weather Service in Like. Diego, referring to Southern California. The coming heat could not only cause an increase in fire activity but also prepare the landscape for the inevitable high winds of autumn. “I’d be surprised if we don’t have a relatively active fire season in September and October,” he said. Further north, Oregon Gov. Kate Brown (D) declared a state of emergency Sunday “due to the imminent fire threat.” “With wildfire behavior increasing across the state and the threat of fire not likely to abate in the near future, it is imperative that we act now to prevent further loss – of life, property, business and our natural resources,” Brown said. he said.
A warm and potentially stormy September An intense and possibly record heat wave is on the horizon as a heat dome begins to build over the western US this week. Excessive heat watches have already been activated for the southern half of California to the northern San Joaquin Valley. “We will likely be in the midst of a full-blown and potentially dangerous heat wave by midweek,” the National Weather Service in Los Angeles wrote in a forecast discussion Sunday. Wider-range forecasts show that much of the month will be warmer than normal. Although the West has not seen the repeated, unprecedented heat waves that occurred in 2020 and 2021, the last half of the summer is still unusually hot. Sacramento, for example, could break its record for the number of days in a year that exceed 100 degrees. Boise has already hit that milestone — topping 100 degrees 22 times this year — the most since city records began in 1875. It’s expected to add to that later this week when temperatures warm up again. 🚨 With just 5 days to go, #Boise #Idaho is poised to see its hottest August since records began in 1875. Boise is likely to finish the month with an average temperature over 80 degrees never before recorded in August. #idwx pic.twitter.com/BIYsbePcyM — NWS Boise (@NWSBoise) August 27, 2022 September – usually a transition month for fall weather – is likely to bring more wind as the jet stream begins to dip further south. Dry cold fronts will push their way into the inland west and bring more organized westerly winds. Stronger “offshore” winds, blowing from the east, become more likely in California as fall progresses. Last weekend, a passing cold front drove several thousand acres of growth into Oregon’s Rum Creek Fire, now over 10,000 acres. It also fanned the flames of the Cherry Gulch fire in northern Nevada, which shot from zero to 15,000 acres in less than a day. “These types of patterns tend to increase as we get closer to fall,” said Gina McGuire, a fire meteorologist at the Great Basin Coordinating Center in Salt Lake City, who noted that dried grasses in northern Nevada and Idaho could fuel rapid spread. of the fire in windy conditions. . There has also been plenty of lightning in Idaho in recent weeks, and wildfires could still occur. “This is a big concern, especially in the higher elevation timber areas,” McGuire said. “That’s something we’re definitely watching, not only with the wind, but also this week with warmer temperatures.”
A quiet end of summer, aided by monsoon moisture In California, about 200,000 acres have burned so far this year — far fewer than the 2.2 million acres burned at this time last year and well below the 5-year average of 1.26 million acres, according to figures from the Department California. Forestry and Fire Protection. The state has yet to record a 100,000-acre “megafire” this year, which has become almost routine in a season of drought and heat intensified by climate change. “We haven’t had many large, active fires at the same time, so our resources are ready to go,” said Robert Foxworthy, public information officer for Cal Fire. “But that possibility exists.” In addition to monsoonal rain in the mountains and deserts, Tardy said, high humidity from monsoonal and oceanic influences has helped suppress fires in Southern California. These benefits could be eliminated by excessive or prolonged heat, as well as dry autumn winds. California could see its first offshore winds in September, which tend to intensify during the fall and have fueled the state’s most destructive wildfires. “Typically we shouldn’t expect July and August to be the bulk of the season in Southern California,” Tardy said. “Our time for the greatest fires is at hand.” While California hasn’t seen a particularly bad fire season so far, the US is still having an active fire year. The National Interagency Fire Center says 47,918 fires have burned more than 6 million acres so far, which is “well above” the 10-year average. Notably, before the monsoon rains arrived, New Mexico saw the two largest wildfires on record in late spring and early summer.
