Well, I did for one. Because it can happen and did once when I was there. And Lucy's data supports it.
SuperVet said it here:
According to Lucy's wunderground data for the last two weeks of August for the last three years, it made it to 100 degrees one day (out of 42 days).
When you were talking about "SoCal" temps of 100 degress I took your meaning as Anaheim since SoCal can vary so much from beach to inland and north to south, and the thread was about DLR. It sounds now like you meant LA when you said SoCal, and I would expect LA to be hotter than Anaheim.
Regarding heat index, to each his own. I never pay attention to it.
I rarely see it in weather forecasts. I do pay attention to wind chill (a little) but still temperature (and wind speed FWIW) means more to me than anything else.

Oh yeah, and humidity too when I am in the midwest, east or south in the summer. I never pay attention to humidity in California or Colorado. To my relative experience the humidity in California is nothing compared to the midwest, Florida, Texas, etc. That is why I ignore it.