To be honest I don't think we get what could be considered extreme temperatures either way here in Sydney, it can get quite hot occasionally in the peak of summer but nothing that would stop you commuting. Like I said 3 weeks ago, the most extreme aspect of my commute is that it's extremely pleasant
At the risk of getting off-topic, a couple of days ago I had a look at the nearly completed new freeway with a totally separated bicycle freeway next to it which will become my new commute - 30 pure, uninterrupted, high speed, velodrome-like miles each way
. It's looking really good, and since it connects with my local MUP and with a MUP at the other end that goes to my workplace I'll have a totally off-road commute!.... I'm even thinking about getting a lowracer recumbent
then I'll
OWN that freeway!!! Any recommendations Mars?... my main criteria is that it has to be FAST!