By cold I mean -26 degrees! This experiment will work when the weather is 0 and below. The other morning we woke up to -36 degree temps and by 10 a.m. it had warmed up about 10 degrees. We decided to show the kids what happens to boiling hot water when mixed with this type of temperature. So, we boiled water on the stove, poured it into a mug and tossed it outside. POOF....it instantly freezes and not one drop of water hits the ground. If you are unfortunate enough to have this cold of weather....give it a try. It is really quite fun. Just hurry and shut the door, don't let that precious heat out!