Thunderstorms and high winds forecast for Boise Monday night

If intense heat and smoky air aren’t enough for you, Boise, how about some thunderstorms?

The National Weather Service in Boise is predicting a 30 percent chance of thunderstorms Monday night. The storm chance comes amid a prolonged dry spell that has seen the city receive just 0.01 inches of rain in July and no significant rain since 0.4 inches fell on June 3.

“It’s probably going to be pretty similar to (Sunday), that’s what we’re thinking right now,” Weather Service meteorologist Sophia Adams told the Idaho Statesman on Monday. “We’re going to have scattered showers and thunderstorms; we’re not expecting a ton of rain with this one.”

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Boise’s chance of thunderstorms and wind

Storms formed in eastern Oregon and southwestern Idaho on Sunday. Although not much rain reached the Treasure Valley, gusty winds and dark skies marked the evening.

Adams said an outflow boundary — the part of a storm that pushes high winds toward the surface — in eastern Oregon produced wind gusts as high as 49 mph. In response, the Oregon Department of Transportation closed a portion of Interstate 84 as smoke from the Durkee Fire was pushed across the highway and reduced visibility.

Similar winds could hit the area Monday night. Alexa Valladolid, a spokesperson for the Incident Management Team working the Durkee Fire, told the Statesman that more highway closures could occur Monday and Tuesday as winds continue to blow smoke from the wildfire.

Adams expects winds in Idaho to reach 55 mph (88 kph) on Monday, while the Treasure Valley is likely to see gusts of 30 to 40 mph (48 to 64 kph).

But the storms won’t be widespread. Like Sunday, the Weather Service expects Monday’s storm system to contain “isolated showers.” The Weather Service gives a 20 percent chance of storms in parts of Boise Monday afternoon and a 30 percent chance in the evening. There’s also no specific timeline for when the storms could hit, but it’s expected to be between noon and midnight.

“We’re expecting a higher probability (of storms) near the southern portions of eastern Oregon and near the Idaho-Nevada border,” Adams said. “And also over portions of west-central Idaho.”

More records and lower temperatures

Boise has been teetering on the brink of temperature records all week, and early Monday morning a new record was nearly broken.

The overnight low in Boise from Sunday night through Monday morning was 82 degrees. The only other time the overnight low was that high was on July 25, 1891, when the overnight low was 83 degrees, according to Weather Service meteorologist Les Colin.

Boise is also on track for a new record for consecutive days with temperatures above 100 degrees Fahrenheit.

If temperatures reach 100 degrees on Monday, it will be the seventh day in a row that the City of Trees has reached the triple-digit mark. With temperatures expected to reach at least 100 degrees every day through Thursday before dropping, Boise could reach 100 degrees for 10 consecutive days – the current record is nine consecutive days, set on four occasions, including in July 2023.

But on Friday, temperatures in Boise will finally become more bearable again.

“We have a low coming in from the Pacific, and that’s going to start the breakdown of the upper spine,” Adams said. “We’re also expecting a pretty good chance of showers and thunderstorms.”

Cooler air will begin to move into Boise on Wednesday night and Thursday. The forecast high for Friday is 93 degrees, while lows on Friday and Saturday are expected to drop to a comfortable 63 degrees.