Meteorological fall is here, but Labor Day weekend in Boise will be pure summer heat
Summer has officially ended — well, on the meteorological calendar.
The hot temperatures baking Boise and Southwest Idaho are going nowhere.
The National Weather Service in Boise issued a heat advisory on Thursday and it will last until midnight Sunday, with temperatures in the high 90s and lower 100s. The advisory does not extend through Labor Day yet, but the weather service forecasts a high of 98 for Monday.
To complicate matters, Idahoans will have to keep their eyes out for smoke.
A hazy layer settled over part of Boise on Thursday afternoon, but the worst was expected to arrive on Friday morning. Westerly winds blew smoke from the Sturgill and Nebo fires in northeast Oregon toward the Treasure Valley, mixing with smoke from the nearby Four Corners Fire, according to meteorologist Dave Gronert.
Southerly winds on Friday afternoon should blow the worst of the smoke out of the Treasure Valley in time for the weekend.
“It won’t be a crystal-clear kind of day after a cold front kind of thing, but at this point, we don’t expect it to be something (big),” Gronert told the Idaho Statesman on Thursday. “But of course, that all changes with fire growth and different fire ignitions.”
The Idaho Department of Environmental Quality issued a moderate air quality advisory for the Treasure Valley on Friday, meaning those “unusually sensitive” to smoke should consider reducing prolonged or heavy exertion outdoors.
Hottest August on record
With the end of August came the end of the meteorological summer. The astronomical summer does not end until Sept. 22 this year. Meteorologists count midnight on Aug. 31 as the official end to make record-keeping easier.
“It’s just because (the date) changes. It’s not a big change, but the astronomical date does change year to year,” Gronert said. “So it’s just to break it up into an easier monthly-based calendar.”
Boise officially recorded its hottest August this year, with an average temperature of 81.9 degrees shattering the old record of 78.7, set in 2001, according to previous Statesman reporting.
The month saw three daily high records broken — including a high of 106 on Wednesday, Aug. 31 — and five dates saw a record-high low temperature, according to the weather service.
Despite such a hot August and a record-high 23 days of at least 100 degrees this summer, Boise didn’t manage to record its hottest-ever meteorological summer. That record was set just last year, at 78 degrees.
The City of Trees’ average temperature this summer was 76.6, putting it in a tie for second, with 2015 and 1869. Records began in 1864.
