Unseasonably cool holiday weekend caps unusually hot summer

Hot runner-up: From June through August, the summer of 2015 has been the second-hottest on record, with an average Boise temperature — factoring in daily highs and lows — of 76.6 degrees. For the all-time record, you need to look back 150 years, to 76.8 degrees in 1865, the National Weather Service reports.

Cooling off: After a Wednesday high of 86 degrees, Boise’s high temperature is expected to plunge to 73 Thursday and 75 Friday. On Saturday, expect a nearly chilly 64 degrees — 19 degrees below the average for the date. Highs Sunday and Monday are forecast at 70 and 76 degrees, well below the seasonal averages.

Raft rental pause: The forecast, including a slight chance of thunderstorms Saturday, prompted Ada County to close rental operations and the Barber Park shuttle service Saturday and Sunday. They’ll reopen Monday, then close for the year.