Many residents awoke to lightning, thunder and showers Tuesday morning as a fast-moving, high-pressure system traveled northward through the Mother Lode.
According to National Weather Service Meteorologist Eric Kurth, the warm storm will likely pass by late morning and will bring triple-digit temperatures to the area later this week and throughout the weekend.
Although some locations within the Mother Lode experienced showers, the rainfall has been too localized to accurately measure, Kurth said.
The California Highway Patrol (CHP) in San Andreas reported one collision Tuesday morning, though it is undetermined if wet roadways were a contributing factor.
“The first rain in a while will cause the roads to be slick and drivers need to reduce their speed,” CHP officer Tobias Butzler told the Enterprise.
The California Department of Forestry and Fire Protection (Cal Fire) responded to four small, single tree/spot fires in Calaveras County and a 1-acre fire near Mountain Ranch on Tuesday. The department initiated a lightning plan (LCA) for the northern portion of the county.
"Activation of the LCA includes the staffing of Blue Mountain Lookout and Air Attack 440 conducting recon for ignitions," stated a news release issued by the Cal Fire Tuolumne-Calaveras Unit.
According to Kurth, thunderstorms are typical within the region during the late summer months due to monsoonal moisture traveling northward from the Southeast.
“We do see this monsoon pattern set up. A lot of times, it’s more east into the High Sierra, but sometimes in the Mother Lode and even the San Joaquin Valley,” Kurth said. “High pressure centered over the Southwest brings moisture up from the Sea of Cortez, basically down by Mexico. There is a lot of warm, moist air over ocean down there, and when high pressure starts steering winds from the south, it can push it into our area.”
The High Sierra may experience additional thunderstorms on Thursday, Kurth said. However, the remainder of the Mother Lode will stay hot and dry once the storm passes, with temperatures not expected to dip into the mid-90s until early next week.
Update 7/23/19: This article was updated to include additional information from Cal Fire.