Los Angeles baked in record temperatures on Monday, bringing sweltering scenes to the West Coast metropolis nearly a month after the end of the main August heat.

As firefighters remained on alert in tinderbox conditions around the outskirts of the city, temperatures hit 113 degrees Fahrenheit (45 degrees Celsius) in downtown, the highest since records began in 1877.

Streets remained unusually empty, as Angelinos sought the shelter of air-conditioned shops, offices and homes.

But in the city center the heatwave, which began at the weekend and is set to last days more, sent some locals frolicking in a walk-through fountain just next to Hollywood's famous Kodak theatre, home of the Oscars.

"There was a spike around noon that bumped temperatures up," said Stuart Seto of the National Weather Service, after the old record of 112 degrees, set on June 26, 1990, was beaten shortly after midday.

Los Angeles firefighters have been on high alert for days for wildfires which can take hold rapidly in the brush and dry woodlands which surround the city.

Although temperatures were high Monday, there was little wind -- giving some relief that any blaze would not spread so easily.

The heatwave comes after a cooler-than-usual summer for Los Angeles, which typically enjoys 300 days of sun a year, albeit with summer temperatures more typically in the 70s and 80s.