McKinney Fire updates: Get info on the McKinney Fire from the U.S. Forest Service. Information line: 530-643-0279 Evacuations: Get the latest info from ZoneHaven. An evacuation center is open at the Weed Community Center. Wildfire cameras: Livestreaming from AlertWildfire.

It's a mixed blessing: Thunderstorms passed over the McKinney Fire near Yreka overnight, bringing rain that limited fire growth but also throwing out lightning strikes that sparked 12 new small fires in the area, officials said Monday morning. These new blazes ranged in size from less than one-tenth of an acre to several acres. "All are being fully suppressed," the U.S. Forest Service said in its latest report on the fire burning near the California-Oregon border.

More thunderstorms are expected today, delivering another chance for beneficial rain — but also for lightning and erratic winds that could exacerbate the blaze. The McKinney Fire has killed two people and threatened and destroyed small towns. 

"While last night’s weather mitigated fire spread, vegetation in the area is extremely dry and the continued threat of thunderstorms and the associated strong, erratic winds could result in increased fire behavior," the Forest Service said. 

National Weather Service forecaster Brian Nieuwenhuis said the Medford office released a weather balloon Monday morning to measure the moisture content in the air and determined that any storms that do reach the region today are likely to bring rain.

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"That measurement of moisture that we see in the air is some of the highest we've ever seen for this time of year," said Nieuwenhuis. "The thunderstorms are going to make rain underneath them, but they're going to make wind all around them, too. You also have your lightning concerns with new starts and the safety of the firefighters."

A chance of thunderstorms continues through Wednesday, but Monday is expected to bring the wettest and most severe storm activity, Nieuwenhuis said.

The McKinney Fire ignited Friday in the Klamath National Forest northwest of Yreka and charred 55,493 acres as of Monday morning, the Forest Service said. The fire started south of Highway 96 but is now burning on either side of the highway, tearing through vegetation and trees that are bone-dry after several years of drought. Firefighters gained 1% containment on Saturday, but crews are now back to no containment.

Two people were found dead on Sunday in a vehicle that burned in the path of the fire. The vehicle was located in a residential driveway along Doggett Creek Road, which is off of Highway 96, west of the community of Klamath River, the Siskiyou County Sheriff's Office said. 

The fire jumped the Klamath River over the weekend and tore through the small town of Klamath River, destroying several buildings, including the Klamath River Community Hall and Oaks Mill trailer park, KRCR reported. 

Klamath River resident Rodger Derry told the TV station that most of the town is wiped out, with only a handful of homes surviving. 

ALSO READ: Dozens rescued from Pacific Crest Trail as McKinney Fire threatens forests

The fire continued to actively back toward residences in the Walker Creek area overnight, and crews worked through the night protecting homes. The southern and eastern edges of the fire, closest to Fort Jones and Yreka, "showed very little growth," the Forest Service said Monday. 

Gov. Gavin Newsom proclaimed a state of emergency for Siskiyou County on Saturday due to the fire. Newsom said the declaration helps access federal aid and unlock state resources for some 2,000 residents who are under evacuation orders. The McKinney Fire is now the largest in the state.

Two other blazes are burning near the McKinney Fire. The China 2 Fire (west of Seiad Valley and south of Highway 96) is about 1,652 acres and didn't see any rain overnight, the Forest Service said. The Alex Fire (at the summit above Doggett Creek) is about 80 acres and received heavy rain. 

Amy Graff is the news editor for SFGATE. She was born and raised in the Bay Area and got her start in news at the Daily Californian newspaper at UC Berkeley where she majored in English literature. She has been with SFGATE for more than 10 years. You can email her at agraff@sfgate.com.