Ready for more heat, Boise? Temperatures to climb back into 100s across Idaho
After a stretch of cooler weather, 100-degree days are returning to Boise and Idaho this week, according to the National Weather Service.
The high on Aug. 4 was 105, but temperatures have been cooler since then. The high on Friday was just 82, and the peak temperatures on Monday and Tuesday this week were 87 and 83, respectively.
But temperatures are expected to spike on Thursday, with a forecast high of 100 degrees, the weather service said. On Friday it’s expected to reach 102, and on Saturday it will be at least 100.
“There’s an area of high pressure that’s bringing another round of hot air in,” Katy Branham, a meteorologist at the NWS Boise office, told the Idaho Statesman by phone.
This year currently has the second-highest number of 100-degree days on record for Boise. The total stands at 17, so just four more days of triple-digit temps would mean 2021 tops the 2003 record of 20 such days.
Doctors in the region have warned residents about the dangerous effects of extreme heat, which may have already caused hundreds of deaths in the Pacific Northwest this summer.
In Idaho, the state has reported eight heat-related deaths this year, according to Niki Forbing-Orr, spokesperson for the Department of Health and Welfare.
July is typically the region’s hottest month, and each day that passes, it becomes less likely that temperatures will reach 100, according to Branham. High temperatures this time of year are normally in the lower 90s.
“I’m not sure we’re going to break (the record this weekend),” Branham said. “But that’s not to say we won’t get another system that could throw another 100-degree day in” later this month.
Of the 17 years with the most 100-degree days, 11 of them have come in the past 20 years, according to the National Weather Service.
On Monday, a United Nations scientific body released a major report on the science of climate change, stating that human activities — largely the burning of fossil fuels — have “unequivocally” warmed the planet. The report also notes that extreme weather, including heat waves, have increased since the 1950s and are also mostly caused by human activity. An analysis of the Pacific Northwest’s major heat wave in July found that it would have been “virtually impossible” without human-caused climate change.
This week’s heat wave in Idaho also is affecting Oregon and Washington state, with temperatures in Portland expected to reach 106, which would set new records there.
Patchy smoke is also predicted for Boise in this week’s forecast, with fumes from the Green Ridge Fire, in eastern Washington, and the Black Butte Fire, in Oregon, flowing into the Treasure Valley.
But that smoke is expected to be lofted, according to Branham, and therefore might not have a significant impact on air quality.
This story was originally published August 11, 2021 at 3:34 PM.
