From my experience with readings in other cars...
Engine bays at speed typically heat up intake temps around 10-15 degrees above ambient.
The big problem is in stop-and-go or idle. A few minutes stopped can raise the engine bay temperature drastically (think 130 degrees intake temp on a 90 degree day). Then when you get going again, you're sucking in all that hot air if you have an open element.
Air intakes on this thing won't get you much but sound and maybe an extra HP or two. I know there will be people that will SWEAR it's SO MUCH FASTER and it's a WORLD OF DIFFERENCE but I really wish those people would practice some science and go prove it on a dyno.
Time and time again, intakes claim to be amazing pieces of equipment and at most yield an extremely modest improvement (and that's ones that suck air from the fender well or some other non-open routing).