Thanks to thunderstorms that rumbled through Jackson County late Thursday, wildland firefighters will likely be busy finding and mopping up lightning-caused fires this Labor Day weekend.

Thanks to thunderstorms that rumbled through Jackson County late Thursday, wildland firefighters will likely be busy finding and mopping up lightning-caused fires this Labor Day weekend.

"This is going to be our major preoccupation through the weekend," Brian Ballou, spokesman for the Oregon Department of Forestry's Southwest Oregon District, predicted Thursday evening.

He was referring to fires that are sparked by lightning but often smolder for a few days before bursting into flame. Fire lookouts and airborne spotters look for telltale wisps of smoke drifting up from the smoldering fires so firefighters can snuff them out before they explode.

Thursday's storms came on the flaming heels of a similar batch of cells Wednesday night that ignited about a dozen fires in Jackson and eastern Josephine counties.

Most of those fires were in the Applegate Valley, with the largest being a 20-acre blaze in the upper Thompson Creek area near Yewwood Gap. That fire, burning in the Rogue River-Siskiyou National Forest, was fought by members of the Rogue River Hot Shots crew assisted by ODF crews.

Nine fires were reported on the forest's Siskiyou Mountains Ranger District, which includes most of the mountains on the south side of the valley. The fires from Wednesday's storm were small and largely extinguished by Thursday evening, according to forest officials.

ODF crews also responded to four fires on state-protected land in the Applegate Valley. The largest was a two-acre fire near Duncan Gap off of Little Applegate Road, followed by a half-acre blaze on Negro Ben Mountain in the Applegate Valley. Fires covering less than a quarter of an acre burned along Upper Applegate Road and in the Mulligan Gulch area near Squaw Lakes.

The Wednesday evening thunder storm sent 65 strikes streaking down on the district, Ballou said.

"We had a downpour here and there," he said. "Where it came down, it helped. One fire (near Talent Thursday evening) had a bunch of hail drop on it. That took care of that."

Reach reporter Paul Fattig at 776-4496 or e-mail him at pfattig@mailtribune.com.