Today at 12:15 p.m. PDT the temperature at Downtown Los Angeles (USC) reached 113°F (45°C), which is the highest temperature recorded downtown since weather recordkeeping began in 1877.
It wasn't quite as hot in the San Fernando Valley. The high temperature at Pierce College reached 110°F.
When I started my run at Ahmanson Ranch it was 106°F. I took two bottles with ice water. One was used to keep my arms, legs and head/neck wet. With the relative humidity low, this was very effective for cooling. I picked a 45-50 minute course that was not too strenuous, and kept the pace moderate.
It was a surprisingly moderate run, but I sure wouldn't want to run out of water or have some other problem when the temperature is that high!