More than 3,000 firefighters are battling six major wildfires in California, the state fire agency says.
One of the fiercest blazes has shut the famous Pacific Coast Highway for the second time in as many days, with a 30-mile (50-km) stretch off-limits.
The so-called Springs fire has reached the coast north-west of Los Angeles, threatening thousands of homes.
Fire crews have tackled more than 680 wildfires so far this year, some 200 more than average for the period.
The Springs fire has tripled in size since Friday morning, burning 43 sq miles (69 sq km), a day after it broke out near Camarillo.
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The blaze has damaged more than a dozen homes, with another 4,000 at risk. No injuries have been reported.
'Very strange weather'
On Friday, a change in wind direction fanned it through coastal wilderness to the beach, then sent it tearing back inland through canyons to neighbourhoods.
Ventura County fire spokesman Bill Nash called it the "worst-case weather scenario".
"In the perfect scenario we'd just hope for the wind to go away, but what happened is the wind just turned around,'' he said.
More than 900 firefighters are combating that blaze, which is about 20% contained.
Firefighters dropped water and retardant on the flames from the air. The fire was fanned by the dry Santa Ana winds, which are occurring unseasonably late this year.
"This is a very, very strange weather pattern for this time of year," said another Ventura County fire spokesman, Tom Kruschke.
"We're seeing fires burning like we usually see in late summer, at the height of the fire season, and it's only May."
On Friday afternoon, the National Weather Service predicted lighter onshore winds of 10-15 mph.
Calmer ocean air could raise humidity levels, helping fight the blaze and eventually bringing rain over the weekend, it is hoped.
The California State University at Channel Islands remained closed for a second day on Friday.
A US Naval air station on the coast has also advised all non-essential personnel to stay home for a second day as the fire edged towards a firing range at the western edge of the base.
Point Mugu spokeswoman Kimberly Gearhart said no ammunition was stored at the range.
North of the fire zone, evacuations of two neighbourhoods were lifted on Friday, but residents were required to show identification to return to their homes, police officials said.
About 200 homes remain under an evacuation order.
-BBC
