Frost? Oh dear, yes that can certainly do it!
I'm glad the sun is out and you are going to get some nice dry weather. For the bugs, you have only a few options when harvest time is close, but Safer's soap is one of them. Spray lightly, avoiding the actual buds if you can, early in the day so it has a chance to dry.
Are you in an area that is normally quite dry and requires heavy mulch? Just curious.
When frost is predicted- you should look at the sky at night and if it is clear, protect your plants. You can toss an old bedsheet over the garden, and then remove it in the morning. The tomatoes will be happy too.