Friday, November 6, 2009

Thunderstorms and a Frank Discussion on Hail vs. Snow

November 6, 2009
5:48 P.M.

All I can say is WOW!!! Unless you've been living in a cave the last 20 hours or so you have no doubt noticed the intense precipitation that has been bombarding the area in the form of heavy showers and thunderstorms.

The radar image above was shot at 11:40 P.M. I was excited about having little homework to do last night and, after brushing my teeth, organizing my binder, and taking a shower, I was in bed by 10 P.M. and fell right asleep. All the sudden, I wake up to heavy rain and wind at 11:50 and a bolt of lightning a quarter of a mile away scares me s***less. Shaken but not stirred, I took a few minutes to stare out the window, admiring the power of nature. I promptly fell asleep shortly afterward. However, I was awakened again by another intense shower at 2:20. Even my mom was excited and rushed to my bed to see if I was awake because she knew that I would love to see the storm. Of course, I was already awake. I looked out the window and contemplated for a short while more before falling asleep again. When I woke up for the last time, at 7:00, it was because of my alarm clock, but if my alarm clock had failed to ring, I would have been awakened anyway by a bolt of lightning that lit up my peripheral vision and I calculated to be less than a half mile away. Talking to a teacher at GHS, she said that that a car behind her at a stoplight was struck by lightning. I also heard that God had spilled his wrath upon the Franklin Quakers in this same medium.
For the rest of the day, we saw more sunbreaks than showers as the atmosphere stabilized somewhat and we were partially rain-shadowed by the Olympics. However, as I type this, a new band of showers has drifted ashore, and there will be thunderstorms embedded in these.
Meanwhile, the coast is continuing to get pounded by huge waves. Waves in excess of 30 feet will continue to crash upon the coast tonight before gradually subsiding tomorrow to the meager height of 25 feet. It will be Friday before we see them approach 10 feet.

Abe Stephenson asked me about hail and snow. His specific question was "when we get hail how close is that to getting snow?? are they related in any way? or is it more like the difference between rain and snow.."
Well Abe, we first have to realize that the two are formed in fundamentally different ways. With hail, supercooled water droplets condense on an object, such as a speck of dust. When this supercooled (below 32 degrees Farenheit) water condenses on the object, it freezes instantly. The object gains area and mass, but it doesn't fall to the ground until it becomes to heavy that the updrafts of the storm carrying it can't hold it up. Since NW thunderstorms are relatively weak, we get small hailstones, as opposed to thunderstorms in the plains which can have very strong updrafts, and, as a result, very large hailstones. Snow also begins as a supercooled water droplet, but after it condenses on an object, it grows into a crystal. After this process has started, the crystal can continue to grow at the expense of the surrounding water vapor. How large it grows depends on the humidity and temperature of the air, while how large a hailstone grows depends more on the strength of the updrafts.
It's pretty complicated stuff, and even I don't understand it fully, but I hope that clears up some stuff.

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