First of all, this website is very useful.. so thanks for the information I have got already :)
Anyway, I know this has roadtrip has been discussed many times before, but I'm after some specific advice about the time of year.
My wife and I are planning a road trip from 20 June -> 5 July. Basic rough itinerary is something like:
Arrive San Francisco from London
and end up in Las Vegas for 4 July before flying back home on 5th July.
Unfortunately this is the only 2-week period we have free (that time of life where everyone is getting married, so most weekends are weddings, stag/hen parties, etc).
I am a bit concerned about the heat this time of year, whether it will be intolerable and prevent us from fully enjoying everything these places has to offer.
Obviously Death Valley will be crazy hot, but we're just planning to drive through, not do any hiking, etc.