Hi guys! My car does the same.
In fact it did about 10 minutes ago. Where I work I can hear it go off about 2-3 times per day. It's probably 75-80 degrees here the car is in direct sunlight. It usually does it between 2 and 4pm. My only doubt if this theory though is that my dad told me he heard it go off late last night 3-4am. That has happened before too. Could it be because it gets cold at night and the dash shrinks???
Thanks,
Nick