A respite from triple-digit heat is expected to continue for a couple more days, but the danger of thunderstorms in the tinder-dry Sierra Nevada has firefighters on their toes.
National Weather Service forecasters expect afternoon highs to remain below 100 degrees today and Tuesday as low pressure draws moist air from Mexico into the mountains.
"We don't see any change in pattern over the next two days," said Carlos Molina, a meteorologist with the National Weather Service in Hanford. "On Wednesday, the wind may change to out of the West and deflect that moisture into Arizona and Utah."
"The moist air keeps us slightly cooler, but once we get drier air and have high pressure settle in, it will allow the temperatures to reach up into the 100s again," Molina said.
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The forecast calls for the mercury to reach 95 degrees today and Tuesday in Merced and 97 on Wednesday and Thursday.
The moisture also fuels afternoon thunderstorms like the ones that blossomed this weekend over the mountains in Tulare and Kern counties. That storm touched off flash floods that hampered fire crews battling the Piute fire in the Sequoia National Forest near Lake Isabella.
The fire has burned more than 37,000 acres since it started two weeks ago.
Fire commanders said a flash flood in Erskine Creek prompted an evacuation recommendation Sunday for some residents near Lake Isabella and forced nearly 60 firefighters to higher ground.
The flood blocked the firefighters from returning to the fire's command post Saturday night and created concerns over weakened trees and washed-out roads in the area.
Fire spokesman Jim Whittington said Sunday the water is at least 2 feet deep in Erskine Creek Canyon and could get worse.
Officials expect water, mud and rocks from a rain-swollen creek to cross one of Lake Isabella's main thoroughfares.
They also warned of possible flash floods on Kelso Valley Road and Thompson Creek east of the lake.
Whittington says at least 2 inches of rain fell on the fire, which contributed to the flooding by burning vegetation that would normally absorb some of the water.
By Sunday, nearly 1,600 people were working on the Piute fire and managed to cut lines around 46% of its perimeter. Full containment is expected by July 20.
A flash flood watch remained in effect through Sunday night in the fire area, but thunderstorms developed as far north as Yosemite.
In Sequoia and Kings Canyon National Parks, Saturday's storm brought little lightning activity compared to the previous two days.
Dave Bartlett, the parks' fire management officer, said Sunday that "dry lightning" Thursday and Friday sparked only a few small fires.
"We have a couple of single-tree fires at high elevations," Bartlett said.
"They don't have any ground fuel under them, so we're just letting them do what Mother Nature intended."
Smoke from the Piute fire and others burning around the state continues to settle in the Valley.
The San Joaquin Valley Air Pollution Control District is predicting the air quality to be moderate today in Merced, Madera and Kings counties, and unhealthy for sensitive groups in Fresno and Tulare counties.
"We expect the dirty air to stay," Molina said.
"If we did get some rain on the Valley floor, it would clean out the air, but that's not likely."