What had been a relatively measured wildfire season became nasty Sunday strong, gusty winds pounded Montana and Northern Idaho on a day where temperatures were very hot and moisture at a premium.

That turned some fires into blowtorches, as more than 20,000 acres burned in just three of the more active blazes, forcing fire crews to adapt to stay safe working in such extreme weather.

Now, firefighters are bracing for more red flag warnings, with continued temperatures into the mid-90s, high winds, and humidities running as low as 7%.

Fires race across land in four counties

The most combined acreage burned on the western edge of the Mission Valley and west of Flathead Lake, an area that is always prone to fast-moving fires given the mix of open fields and forests.

The Niarada Fire is estimated to have burned about 5,000 acres west of Elmo, crossing Highway 28 in an area that was already scorched during last year's big Elmo Fire as it pushed northeast. The nearby Mill Pocket Fire had burned 100 acres west of Narada.

The Middle Ridge Fire burning west of Ronan at Sloan's Bridge has burned approximately 7,000 acres. CSKT Division of Fire says firefighters and aircraft were working the fire Monday.

The Communication Butte Fire had burned about 400 acres north of Dixon in the steep Ferry Basin. Crews were emphasizing safety in dealing with the flames.

The Big Knife Fire, which was started by lightning above Arlee, made a run in the high winds  Sunday, creating "extreme conditions" as it grew to 3,000 acres.

All four of those fires were generating considerable smoke.

Firefighters maintain progress on other fires

Fire crews have 6% containment now on the Colt Fire, which has burned over 6,000 acres northwest of Seeley Lake. Crews were able to hold control lines despite the high winds.

Crews working the remote Bowles Creek Fire above the Skalkaho in Bitterroot County were able to maintain 3% containment on that fire, which has burned just 1,700 acres.

Two major Idaho fires sending smoke in Montana

The biggest blow-up in Sunday's winds happened on the Middle Fork of the Salmon River northwest of Salmon, Idaho where the Elkhorn Fire went on a fierce run, burning 8,000 acres Sunday alone, sending smoke and ash in the Southern Bitterroot. It now totals at least 10,000 acres and is causing safety concerns for river floaters, hikers and the handful of backcountry ranches and airstrips along the river.

And the Hayden Fire continues to burn southwest of Salmon, having consumed over 18,000 acres. But fire teams have managed to hold containment lines at 5%.

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