i may have used the wrong terminology.
as a liquid, it is always cold. on a 90 degree day, stick your hand in a bucket of it, and it'll be cold.
like i said......i do not know why it is, and am fairly sure that there's someone here that can tell me why it is.
some of us here can admit when we're wrong, or don't know something..... 
Mmmm... couple things it could be. First is that a bucket of gas left in a sunny and warm spot will eventualy just become an empty bucket. Usualy we would put a bucket of gas on the ground in a cool, shady, out of the way spot. So it could be cold simply from being kept on the cold floor in the back corner of your garage. I suspect though you're sensing the cold sensation you feel imediatley after pulling your hand out of the bucket from the rapid evaporation of the liquid to gas on your skin into vapor (much the same with rubing alcohol, it feels really cool as it evaporates off your skin). Liquids that rapidly evaporate do this to skin, precisely why I don't remember from that day in junior high science class, I think it was called thermal discharge or something.
Edit: dern it, Skuzzy beat me to it.
"In order for a liquid to change into a gas (boil or evaporate) it must absorb energy to make its molecules vibrate fast enough to escape. It does this from its surroundings, in this case your skin. It is called the latent heat of boiling."
Thanks for the junior high science class flashback, my head hurts now.
