Boise, Idaho – Temperatures across southwest Idaho are expected to soar past 100°F on Tuesday, with Boise likely hitting 104°F by mid-afternoon, prompting a heat advisory that will remain in effect until 8 p.m. MDT.
According to the National Weather Service in Boise, the advisory covers the Lower Snake Plain, Treasure Valley, and Weiser Basin—including the cities of Boise, Caldwell, Nampa, Ontario, and Fruitvale. The alert runs from 11 a.m. MDT (10 a.m. PDT) to 8 p.m. MDT Tuesday, with highs between 101°F and 104°F across the region.
Residents in the Treasure Valley are urged to take precautions against heat-related illnesses. Hot weather can be especially dangerous for the elderly, young children, and pets. The Occupational Safety and Health Administration recommends limiting outdoor activity, drinking plenty of water, and scheduling frequent breaks in shaded or air-conditioned areas.
Communities such as Nampa, Council, and Nyssa should prepare for peak heat between 2 and 6 p.m., when humidity is low and sun exposure is most intense. Strenuous outdoor work should be rescheduled for early morning or late evening hours.
The heat advisory will expire at 8 p.m. Tuesday, but above-normal temperatures near 100°F are expected to continue through midweek.
📅 Five-Day Forecast for Boise, ID:
- Monday: Sunny, high near 99°F. Calm wind becoming west 5 mph.
- Tuesday: Hot, high near 104°F. Heat advisory in effect.
- Wednesday: Sunny, high near 99°F. Partly cloudy overnight.
- Thursday: 20% chance of showers. High near 93°F.
- Friday (Independence Day): Mostly clear, high near 89°F.
