I have seen crocus coming up through the snow in Flagstaff, AZ (USDA zone 5), so they are pretty hardy critters. If they are buried deep next Tuesday, though, you might have to wait until 2013 for more flowers. It shouldn't severely damage the plants, though.

Agree with Tug. We often have the same weather being neighbours and my bulb plants have usually survived after being 'tricked' into appearing too soon.

Our crocus have been up and in flower for several weeks now, due to the mild winter we've been experiencing. If we suddenly get a long period of frost and snow the flowers will die but the bulbs will be fine.

Thank you for my answers.