You could always try to move a few, but leave some just in case. I am not familiar with your area or zone. If you move them now you should just lose bloom.

Aren't you a bit too frozen to try digging around if you are in zone 5?

Aside from that... I can say that I have overwintered irises I've gotten on clearance in pots and put them in in the spring once the soil could be worked and not lost them. I haven't done this often though, so I don't know if I just lucked out with what I planted, or if it's actually ok to do so.

If you have a whole bunch of irises, that should mean you got a bunch of rhizomes. So as littlebit said, move a few, and see what happens.

I live in Dallas and in my garden I plant irises all the time. I don't wait for a special time. I break up the rhizomes and try not to plant to close to the other one for overcrowding purposes. Mine are in full sun and it can get pretty hot. Not right now cause we have snow on the ground,

Thanks all! Whoops, meant to say Sunset Zone 5 (Western Washington), not USDA Hardiness. Not frozen, just soggy :). Moved a couple and they seem to be doing alright, but we've had one heck of a warm winter.