To take part of any events in the parade you have to registered and signed in and picked up your badge and car # to put on the vehicle and signed the waiver form. For what is left I would check the schedule:
Parade 2014 Schedule Highlights
http://parade2014.pca.org/docs/form_event_gantt2014.pdf
but I think again you need to have pre registered for any of the events etc to be signed up for them... I dunno if any are open or available at this point..
I'm no longer down there right now but generally speaking Monterey / Carmel is cold and windy... other than inland where it can get warm and sunny in the afternoon...but generally it feels more like downtown bay area at the coast...say along highway 1 etc... Laguna Seca is inland a bit so that might get warm during the day and then cold at morning/night. having multiple Layers is good idea.