Journal Entry

Learning My First Cold Weather Lesson

This is a question I never really thought about. After all, I live in Phoenix Arizona and we don't get VERY cold air. What do we mean by VERY cold? I'm talking -20 degrees Fahrenheit or colder. Burrrrrr - I'm cold just thinking about that number. So when a group of the teachers started going outside to throw steaming hot water up into the air I had to go see what all the fuss was about. http://

According to Mark Seeley, a climatologist at the University of Minnesota, the reason why the hot water turns into snow is because the air is dry with hardly any water vapor. The steaming hot water in my cup is already releasing water vapor. Tossing it up in the air speeds up this process by increasing the surface area of the water by dispersing it into smaller droplets. The water vapor precipitates into snow. Totally cool right. Just make sure that you do this in really cold temperature (greater than -20ºF) and never throw scolding hot water over you or at your friends.

Comments

Anonymous

I am wondering if the temputure could be up to 50 degrees fahrienheit because that is still cold weather!

Sian Proctor

That's a great question. While I was in Alaska I was told that the air has to be supercold and at least -30 degrees F to cause the water to change rapidly into snow. When I did this video, the temperature was a little warmer then -30 so the effect wasn't as great as I was hoping for.
Thanks for the question! Sian

Carol Scott

Welcome to Fairbanks Sian! Looking forward to your description/explanation of the throwing-water-in-the-air experiment!