National Weather Service upgrades Spokane to excessive heat warning, consecutive 100-degree days likely

Jun. 25—The National Weather Service upgraded Spokane to an excessive heat warning starting Friday that will last until Thursday, reflecting the magnitude of what forecasters are saying could be the most severe heat wave in local recorded history.

NWS Spokane announced the excessive heat warning Thursday afternoon and said it has "high confidence" that temperatures will reach 100 degrees every day from Sunday all the way to Thursday.

Forecasters want Spokane residents to know that this will not be like any heat wave they've experienced before.

"This has the potential to be the most severe heat wave since records in Spokane have been kept," said Travis Wilson, science and operations officer at NWS Spokane.

NWS meteorologists said residents should be wary of the temperatures during the day and the abnormally warm low temperatures at night. The natural "nighttime air conditioning" that many rely on to cool down their house while they sleep will not be as effective.

The NWS forecasts the overnight lows in Spokane to be 73 degrees on Monday and Tuesday.

The extreme temperatures and dry conditions spurred the Washington State Department of Natural Resources to issue warnings and new burn restrictions for some areas. Effective Friday, rule burning isn't allowed in the Highlands and Methow Fire Danger Rating Areas of northern Washington, nor are campfires unless they're in an approved site.

Outdoor burn bans on DNR lands were already in place for all of Washington except five counties on the West Side as of Wednesday. The agency also raised the fire-risk levels from low to moderate for many counties west of the Cascades.

Consecutive days of excessive heat without cool temperature breaks create significant extra risk for heat stress and stroke.