A frost for a short time would not burn the bulbs. The soil keeps that insulated. Dig your bulbs and rinse them with a hose and cut off all the stems. Place them in a large bowl or an old cookie sheet works great. Good bulbs should feel very hard. Throw out any which feels the least bit spongy. Do not pile them deep in a small container, the ones on the bottom will mildew. Place them in an area which has good air circulation for about 2 weeks. Then store them in your house inside a paper bag until next Spring's planting time. Do not put them in a refrigerator. It so happens I just dug mine up last week and dried them. I have used the same bulbs for 3 years now. I am located in zone 7, Southside Virginia. Good luck with yours and happy gardening.

Thanks! I really appreciate this and wish I could have gotten this info a few days earlier. I just left home to be gone for a couple of weeks. We'll see what they feel like when I get back, but the forecast isn't good! :(