jiffer... good news... I live in San Diego and the temps for next Sat are supposed to be back into the low to mid-80's! Plus you'll have breeze on the coast...

the only real climb is Torrey Pines... and if you're already doing 3500ft in a ride, you'll totally be fine! I ride the coast regularly and the route is not bad at all...

hope you have a great century and a fun and safe ride!