The summers where I live get very hot for California (next few days its 101, 104, 104, and 103). And to top it off, it doesn't cool off much at night this time of year.
Sounds horrible, right? But I actually kinda like it. Why? I always know exactly what to wear in all circumstances at all times of the day: Shorts and a t-shirt. No long pants, no long sleeves, no jackets or sweaters or hoodies... just shorts and a t-shirt. Am I going to be indoors or outdoors? Am I going to be out mainly in daylight or after dark? What's the temp supposed to be in the morning compared to the afternoon? Doesn't matter. Shorts and a t-shirt.