The Treasure Valley faces a dangerous combination of extreme heat, critical fire weather conditions, and widespread smoke through Saturday before a gradual moderation begins Sunday. Temperatures will remain well above 100 degrees Saturday before slowly trending back toward normal early next week.
Sizzling heat continues in Scott Dorval's video forecast
Dangerous Heat and Critical Fire Weather Saturday
Saturday will bring another day of dangerous heat to the Treasure Valley, with highs near 101 degrees under mostly sunny skies. Critical fire weather conditions will persist through Saturday evening as a dry slot sets up over southwest Idaho, pushing relative humidity values into the single digits across much of the area Saturday afternoon. Breezy northwest winds will develop through the Baker Valley corridor into the Snake River Basin Saturday evening, with gusts in exposed areas up to 40 mph. These conditions will be particularly dangerous for any new fire starts.
Widespread Smoke a Major Concern
Widespread smoke will be a significant concern through the weekend, driven by new large fires burning in eastern Oregon and the Owyhees. Northwest winds developing Saturday evening will funnel smoke from central Oregon down the Baker Valley into the Snake River Basin, impacting the Treasure Valley both Saturday and Sunday. Smoke will be most widespread Saturday afternoon and evening before gradually improving Sunday.
Gradual Cooling and Improving Conditions
Temperatures will cool a few degrees Sunday to near 96 degrees as the pattern begins to moderate. Smoke will gradually improve Sunday, though areas of smoke will linger through the day. The critical fire weather threat will diminish Sunday as winds ease and humidity values recover slightly.
Extended Outlook: Near-Normal Temperatures Before Warming Again
High pressure over the Four Corners region and troughing off the British Columbia coast will keep the Treasure Valley under southwesterly flow through the coming week. This pattern will keep monsoon moisture south and east of the area, maintaining hot, dry, and breezy conditions. Temperatures will be near normal to start the week before rising to around 5 degrees above normal by Wednesday. A warming trend will then continue late in the week as the Four Corners high shifts west over the Great Basin, pushing highs back toward 102 degrees by Thursday and Friday.
Central Idaho Mountains
The central Idaho mountains will see a slight chance of thunderstorms this evening over the Boise and Owyhee Mountains, with gusty outflow winds possible. The mountains will also be impacted by widespread smoke through the weekend. Monsoon moisture will remain largely south and east of the central mountains through the extended period, keeping thunderstorm chances limited.
Tonight
Widespread smoke, mainly before 7pm. Mostly clear, with a low around 69. Light wind.
Saturday
Widespread smoke, mainly after 3pm. Sunny and hot, with a high near 101. Light wind.
Saturday Night
Widespread smoke, mainly before 9pm. Mostly clear, with a low around 66. Northwest wind 5 to 10 mph becoming light and variable after midnight.
Sunday
Areas of smoke. Sunny and hot, with a high near 96. Calm wind becoming west northwest 5 to 7 mph in the morning.
Sunday Night
Areas of smoke before 7pm. Clear, with a low around 63. Northwest wind 5 to 7 mph becoming calm after midnight.
Monday
Sunny and hot, with a high near 96.
Monday Night
Clear, with a low around 63.
Tuesday
Sunny and hot, with a high near 98.
Tuesday Night
Clear, with a low around 64.
Wednesday
Sunny and hot, with a high near 99.
Wednesday Night
Clear, with a low around 65.
Thursday
Sunny and hot, with a high near 102.
Thursday Night
Clear, with a low around 66.
Friday
Sunny and hot, with a high near 102.
