Upper-level disturbances carrying moisture from the south thwarted expected triple-digit temperature readings Sunday.

Upper-level disturbances carrying moisture from the south thwarted expected triple-digit temperature readings Sunday.

The zig in the weather pattern, however, raised the possibility of dry thunderstorms in Northern California and Southern Oregon this week.

Hail-spewing storms centering on Talent last week are unlikely to return. Instead, said Dan Weygand, a meteorologist with the National Weather Service, isolated thunderstorms are more likely to trigger fires in the Cascades and to the east.

"The bigger concern is for lightning strikes creating fires in our area," Weygand said.

Today may not bring significant strikes, but there is a 10 to 20 percent chance of such storms throughout the rest of the week, he said.

For the better part of Sunday, the Rogue Valley experienced unseasonably mild temperatures. At noon, the Weather Service had an 81-degree reading for Medford. Eventually the mercury reached 95 degrees, well below the forecasted high.

"We had a little upper-level disturbance coming up from the south that brought moisture with it," Weygand said. "It provided a thick blanket of cirrus clouds and kept things colder until the early part of the afternoon."

The moisture, however, exited the Rogue Valley heading northeast — a welcome occurrence for firefighters in the eastern half of the state.

With the moisture leaving the area, however, the clash of low pressure, centered west of British Columbia, and a strong pressure ridge centered over the Desert Southwest will create thunderstorm activity throughout the week.

"Up until now, most of the moisture has been getting into Nevada," Weygand said. "It will swing into the Northwest, mostly on the Cascade crest and eastward."

"We'll still see hot temperatures this week, in the upper 90s, and exceeding 100 degrees in some places," he said. "But the disturbance might shave a couple degrees off what was expected."

The National Weather Service forecast for today is 103 in Medford, 100 in Ashland and 105 in the Klamath River Valley around Happy Camp.

"The normal high for Medford this time of year is in the 90s and our hottest days of the year are right around Aug. 1," Weygand said.

The Northwest Interagency Coordination Center reported the Ferguson fire north of Klamath Falls, which appeared Friday, was checked at 200 acres.

Reach reporter Greg Stiles at 541-776-4463 or business@mailtribune.com. Follow him on Twitter @GregMTBusiness, friend him on Facebook and read his blog at www.mailtribune.com/Economic Edge.