ABC News June 21, 2016

Winds and Hot Temps Fuel Fast-Moving Fires in Southern California

WATCH: Aircraft Drop Water to Prevent Two California Wildfires From Merging

Erratic winds are feeding fast-moving fires in Southern California Tuesday after days of extreme heat.

Twin wildfires called the reservoir and the fish burned through the San Gabriel Valley area near Los Angeles, forcing evacuations in the area.

Jonathan Alcorn/Reuters
Smoke from two fires burning in the Angeles National Forest rises with the downtown skyline in the foreground in Los Angeles, June 20, 2016.

The fires have burned 5,400 acres combined, and neither has been contained as of Tuesday morning, according to Angeles National Forest officials.

Some firefighters told ABC News these were the hottest conditions they have ever had to work under.

The Angeles National Forest posted video of the reservoir fire Monday afternoon:

And an officer with the Los Angeles County Sheriff's Information Bureau posted video of the fish fire Monday night:

With the region suffering from triple-digit temperatures, fires have threatened areas north and south of Los Angeles, too. In the San Diego County town of Potrero, a blaze called the border fire tore through about 1,500 acres this weekend, forcing evacuations.

Hayne Palmour IV/San Diego Union-Tribune via AP Photo
Upland firefighters, from left, Nima Homayounieh, Joseph Armendariz, and Capt. Joe Burna, watch as flames burn toward Highway 94 near Potrero, Calif., June 20, 2016.

In the Santa Barbara area, the sherpa fire, which began last week, has burned more than 7,000 acres.

Mike Eliason/Santa Barbara County Fire Department via AP Photo
A British Aerospace BAe-146 belonging to Neptune Aviation makes a Phos-Chek drop, June 18, 2016, on wildfires in Santa Barbara County, Calif.

Los Angeles is not alone in its fight against Mother Nature; more than 20 fires are burning across eight western states.