On 12/24/2007 11:28:36 AM, Jose wrote:

But when I was pretty much done, I noticed there was frost on the wings,
which hadn't been there before.

I have experienced this a few times. Two memorable times were once after
landing at Niagara Falls airport and once after landing in Plattsburgh, NY.
In these two cases it was after dark, the sky was clear, and the temperatures
were very cold (perhaps around 0 to -10 degrees F). In each situation the
aircraft's wings and horizontal stabilizer frosted over within minutes of
landing.

--
Peter