If record-breaking heat wasn’t making life miserable enough in Cache Valley and around the region, the week’s end brought a thick layer of smoke that put air monitors well into the red zone.
Although two wildfires are burning in western Box Elder County, the vast majority of the smoke is coming from an epic outbreak of lightning-caused fires this week in California. According to a report in The New York Times, more than 550 fires covering 771,000 acres were overwhelming fire-control crews and forcing widespread evacuations Friday afternoon. The state has seen about 12,000 lightning strikes in a period of just a couple of days.
One measure of hazardous particulate pollution, PM 2.5, has risen steadily since Wednesday in Cache Valley, with readings reaching 91.9 ug/m3 (micrograms per cubic meter of air) on Friday afternoon. The red level covers readings from 55.5 to 150.4 ug/m3.
Jon Meyer, a meteorologist with the Utah Climate Center at Utah State University, noted the current air quality is rivaling that of bad wintertime inversion days but added, “The good news is that typically, daytime heating will help mix out some of the smoke choking the morning air, so conditions do tend to improve through the day but then again get worse overnight.”
Meyer said the relatively small fires burning west of Cache Valley — one in the Hansel Valley north of the Great Salt Lake and the other just west of Park Valley — are adding “near-surface smoke alongside the more impressive smoke plume coming in from the vast amount of California fires.”
An unusually hot, dry summer has aggravated the fire season across the West, though Northern Utah has been largely spared. Meyer cited several tied and broken daily temperature records for Logan in August, but said the summer overall has not been significantly hotter than in other years over the past two decades.
“It’s been the individual heat waves we’ve seen this summer that have pushed this year into unusual and miserable territory,” he said.
August opened with a heat wave that saw two days of record 103-degree temperatures on Aug. 1 and 2, plus one record-tying temperature of 100 degrees on Aug 3.
These were records for those calendar days, but the 103-degree reading at the Logan/Cache Airport weather station on Aug. 2 was also the second hottest temperature ever recorded there for any day — one degree shy of the all-time high of 104.
The month’s latest heat wave, which has spanned the past week and looks to continue through next week, saw one single-day record, a 99-degree high on Monday, followed by a record-tying single-day temperature of 98 degrees on Tuesday.