Yes Rick, that's been my observations. I think I can explain this in three phases. First, when lilies first peak thier noses up (about an inch or so) the are still frost or freeze resistant well below 32' degrees. Second, as growth pushes further upward to 2, 3, 4 inches, it looses it's frost or freeze resistance rapidly and becomes most vunerable when the new stem opens up with a dense floret of leaves on the top. This is the most critical or most vunerable phase. I've observed many times where damage can occur at frost conditions at temperatures even above 32'F at this stage when there is a heavy dew. I believe it is this excess moisture that forms and is trapped within this tightly packed floret so it doesn't necessarily have to freeze to get a 'mushy top'. Third, once the stem grows taller and the leaves become more and more seperated as individuals, they become more and more unlikely to be damaged. Probably due to the physical nature, better air circulation is achieved; but I believe also that new tender growth is becoming more aclimated (tougher) and freeze resistant, well before bud stage. By Fall, of course, some lilies are so freeze resistant that a 'deep' freeze may not even freeze them.
There are Divisional differences with Spring frost resistance, Regales are by far the most susceptable, Asiatics the least.
My observations were taken over a 20 plus year period. You know I cover for frost, but I can't get them all. Some I miss, some I forget and sometimes I just plain get caught with my pants down with an unexpected frost not even I could predict locally so I've had plenty of opportunity to see what happens over the years. And, I should add, there are some which I don't care if they freeze or not.
So, even tho some garden temperatures in upstate New York will go below 32'F this morning, there most likely will not be any damage considering how far along they are in growth. We'll see what happens.
Picture added: I-390 Genessee Expy @ Rochester, NY. Frost on the grassy median. If you zoom in at 200% you can see a couple state patrol guys checking for speeders coming around the curve (upper left corner
