Thats why I live in Tassie. It's cold ALL the time! ha ha ha. Good crisp air is awsome for power production and throttle response.
It would be hard to know what effects humidity (if any) would have in such a warm climate.
If your worried about intake temps and humidity, throw the car on a chassis dyno in summer and give it a good work out. Then log the coolant, oil and air intake temps as well as afr's/detonation.
If your so inclined- install a larger intercooler and oil cooler with a thermostat. Also if the car is auto, invest in a trans cooler if your going to give the car a hard time.