Extreme heat believed to be the cause of large fish die-off at Lake San Antonio.

The County of Monterey put out an unusual announcement today, as the Central Coast is in the throes of a heat wave. 

There is a large fish die-off at Lake San Antonio, in South County, but it's not believed to be from any toxicity—it's the heat. 

The county's announcement states, "There is a large fish death event happening at Lake San Antonio. The California Department of Fish and Wildlife has been advised, and believes this die off to be the result of the extreme temperature change, causing oxygen depletion in the water…

"There is not [believed] to be any risk to humans or pets. Lake goers can still fish but people are advised to leave the dead fish alone."

Air temperatures at Lake San Antonio are forecast to climb above 100 degrees for the next five days.