Weather
Treasure Valley Weather Oct. 16–20: 70s Return After Frost
BOISE, ID — Idaho's Treasure Valley is heading into a warmer stretch of October weather, with temperatures climbing into the upper 70s Friday following a chilly start to the week that prompted a frost
By Elliot Vaughn · 2026-10-14T10:58:35.567Z
BOISE, ID — Idaho's Treasure Valley is heading into a warmer stretch of October weather, with temperatures climbing into the upper 70s Friday following a chilly start to the week that prompted a frost advisory across the region.
According to the National Weather Service in Boise, a Frost Advisory remained in effect until 10 a.m. MDT Wednesday, Oct. 14, covering portions of southwestern Idaho and eastern Oregon, including Boise, Nampa, Caldwell, Ontario and Nyssa.
Temperatures between 33 and 36 degrees were expected to produce frost, with a few locations potentially falling below freezing. Forecasters warned that sensitive outdoor vegetation could be damaged if left unprotected.
The advisory is scheduled to expire well before the five day outlook begins Friday, with a considerably warmer pattern expected.
Temperatures Climb Into Upper 70s Boise is expected to reach approximately 70 degrees Thursday before warming to 77 degrees Friday, marking the warmest afternoon in the five day forecast.
Sunshine should dominate Friday, with south southeast winds developing during the afternoon and gusts potentially reaching 23 mph.
The warmer conditions will continue into Saturday, when Boise is expected to reach 76 degrees under sunny skies.
Overnight temperatures will also moderate compared with Wednesday morning's frost producing conditions, with lows near 50 degrees Friday night and 46 degrees Saturday night.
For Treasure Valley residents, the shift provides a stretch of favorable weather for outdoor activities following the midweek cold.
Cooler Weather Returns Early Next Week The weekend warmth will gradually ease beginning Sunday, when Boise's afternoon high is expected to reach approximately 72 degrees.
Monday brings continued mostly sunny conditions and a high near 70 degrees, maintaining relatively mild afternoons.
A more noticeable change arrives Tuesday as temperatures fall toward 60 degrees, accompanied by mostly cloudy skies and a 20% chance of showers.
That represents a 17 degree decline from Friday's projected high.
While the broader Treasure Valley experienced the frost advisory, the daily temperatures below specifically represent Boise. Conditions in Nampa, Caldwell, Ontario and other surrounding communities may vary.
Five Day Weather Outlook: Oct. 16–20 Temperatures below represent National Weather Service forecasts for Boise, Idaho, illustrating the expected trend across the Boise area of the Treasure Valley.
Friday, Oct. 16: Sunny and warmer, with a high near 77°. South southeast winds developing during the afternoon, with gusts up to 23 mph. Mostly clear overnight, with a low around 50°. Saturday, Oct. 17: Sunny and warm, with a high near 76°. Mostly clear overnight, with a low around 46°. Sunday, Oct. 18: Sunny, with a high near 72°. Mostly clear overnight, with a low around 49°. Monday, Oct. 19: Mostly sunny, with a high near 70°. Mostly cloudy overnight, with a low around 44°. Tuesday, Oct. 20: Mostly cloudy and cooler, with a 20% chance of showers. High near 60°. Overnight temperatures unavailable.