Wildfires plague the US West amid a scorching heat wave and high winds

At least a half-dozen homes lay in ruins after one of many dangerous wildfires in the West suddenly swept into a Southern California neighborhood during a blistering heat wave.

Six homes were ravaged and seven damaged when the fire sparked by fireworks erupted Sunday afternoon in a hilly area of Riverside, a city about 60 miles (95 kilometers) east of Los Angeles, authorities said at a media briefing Monday evening.

The blaze scorched just under a square mile (2.6 square kilometers).

Resident Noel Piri and his wife were away when they got a call about a fire in the neighborhood, rushed home and rescued their dog. Unfortunately, their house was in flames when firefighters arrived, The Press-Enterprise reported.

"It was kind of sad to see the house was gone," Piri told the newspaper after rummaging through the remains of the newly remodeled house.

Riverside hit 102 degrees (38.9 Celsius) on Sunday amid a heat wave that has been largely focused on the interior of California and is expected to last through much of the week.

Many other fires were also burning throughout the state, including one that started Saturday and rapidly expanded to more than 4 square miles (10.3 square kilometers) on the border of Lake and Colusa counties, northwest of Sacramento. Containment reached 25% on Monday.

More than two dozen fires also were burning in the Pacific Northwest and Idaho, where lightning ignited more blazes in Oregon over the weekend amid extremely dry and hot conditions. The largest blazes were active in rural areas of eastern Oregon and Washington, and smoke was impacting air quality in those places as well as into Idaho.

Authorities evacuated the town of Huntington, Oregon, with a population of about 500, and temporarily closed a stretch of Interstate 84 late Sunday after thunderstorms caused a massive smoke column to collapse.

The implosion of the plume sent winds of 50 mph (80 kph) in every direction, raising fears the fire would jump I-84, the Baker County Sheriff's Office said in a Facebook post.

Evacuation orders remained in place with extreme fire behavior prompted by high winds pushing the flames Monday afternoon, authorities said. The fire covered more than 272 square miles (704 square kilometers) with no containment.

Monday afternoon, the Baker County Sheriff's Office said three new fires had started northwest of Huntington and were prompting evacuations, as well as the closure of I-84 in the Durkee area.

Officials with the Malheur National Forest in neighboring Malheur County closed it to public use on Monday, citing the active wildfires, "extremely unfavorable" weather conditions and limited firefighting resources.

Meanwhile, another fast-moving fire started Monday afternoon farther west on the Oregon side of the Columbia River Gorge, where a wind advisory was in place until midnight for gusts up to 50 mph (80 kph) or more. The Wasco County Sheriff's Office issued mandatory evacuation notices for an area up to the edge of Mosier, with everyone in the town of more than 400 told to be set to evacuate.

Large wildfires can generate huge plumes of smoke and ash that can rise more than 5 miles (8 kilometers), depending on conditions such as the terrain, weather and temperature. The columns can collapse when the amount of heat over the fire drops — from changing fuels or weather — and reduces the updraft, or when strong winds sheer off the top of the column.

In the most extreme cases, smoke columns can be topped with "fire clouds," or pyrocumulus clouds, that look much like the thunderheads that develop before a big thunderstorm.

It's not unusual for a smoke column to collapse, and some fires go through multiple cycles of column collapse and regeneration in a day, according to the Southwest Fire Science Consortium.

Authorities in Utah, meanwhile, lifted evacuation orders for a wildfire in Salt Lake City that threatened neighborhoods near the state Capitol over the weekend.

The blaze began Saturday and grew to about 200 acres (80 hectares). The evacuation order was lifted late Sunday, but officials cautioned that residents needed to remain ready to evacuate, with the fire only partially under control as of Monday morning.