Boise, Idaho – Thunderstorms building across Idaho Tuesday will deliver heavy rain, raising the risk of flash flooding and travel disruptions just days before the Labor Day weekend. Emergency managers warn drivers and hikers to stay alert, especially near recent burn scars and low-lying roads where flooding can occur within minutes.
According to the National Weather Service in Boise, the highest threat comes Tuesday afternoon through Wednesday as monsoon moisture fuels repeated downpours. Burn scar zones, including the Wapiti Fire near Grandjean, ID, and the Lava Fire near Cascade, ID, are especially vulnerable to dangerous flash flooding. Isolated storms may also impact southeast Oregon and areas along the I-84 corridor near Boise, slowing commutes and early holiday travel.
Showers are likely to continue into Wednesday, with locally heavy rainfall possible. Drivers should avoid crossing flooded roadways, and residents in flood-prone neighborhoods should prepare to move vehicles or valuables to higher ground. Power outages and reduced visibility may also occur under stronger storm cells.
Conditions improve by Thursday, with drier and warmer weather returning in time for the Labor Day weekend. Still, officials urge travelers to monitor updates, as even brief downpours can cause delays.
Five Day Forecast for Boise, Idaho
- Tuesday: Chance of thunderstorms after 3 p.m., high near 89. Heavy rain possible.
- Tuesday Night: Showers likely, low near 66.
- Wednesday: Showers and thunderstorms, high near 80. Heavy rain possible.
- Thursday: Slight chance of showers, partly sunny, high near 81.
- Friday: Sunny, high near 86.
- Saturday: Sunny, high near 88.
- Sunday (Labor Day Weekend): Hot, sunny, high near 90.
