Overheating

What is your question?

On a hot day out of the blue truck started to beep , prior to that the a/c was blowing hot x, I looked and saw it was in the hot zone , I stopped , popped the hood and saw no indication of hot engine , started it up again and it was fine to drive , no overheating and drove it home ????

What makes this problem better or worse?

Unknown

How long has your 2007 Ford F-150 had this problem?

Just today