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Snow, Sleet, Hail, & Freezing Rain Facts
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When I was young, I loved
snow for many reasons. Perhaps the biggest reason I loved snow was that it created the potential for getting a day
off of school. Of course, sledding, building snow men, snowball fights, and just watching the snow fall were great
pastimes, especially if done while enjoying a day off school. Unfortunately, where I grew up in Annapolis,
Maryland, there was never enough snow for my liking. I recall vividly laying in bed on a school morning listening
to the AM radio hoping to hear a report of a school closing. Usually, it would be raining at my house while the
announcer would report that kids at schools in the northern and western counties would be off for the day. Only my
parents were happy about that.
Later in life, I still enjoy the snow, but after living for years in Vermont
and upstate New York, my definition of great snow is mostly that which I can see on the distant mountain tops
while my driveway is clear. The days of having a four-month-long layer of packed snow on my driveway and road in
front of the house is past. I sure would have loved it forty years ago, though.
| How Much Snow is Made With 1" of Rain? |
| Average Snow:
10" (25 cm) |
| Heavy, Wet Snow:
4 to 5 (10-13 cm) |
Dry, Powdery Snow: 15 (38 cm)
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| Definitions |
Sleet: Precipitation of small, partially melted
grains of ice. Sleet occurs only during the winter, while hail, a different form of icy precipitation, may
fall at any time of the year.
Freezing Rain:
Precipitation that begins as snow falling from a cloud towards earth. It melts completely on its way down
through a layer of warm (above freezing) air and then supercools in a small layer of cold air just before
it impacts the surface. Due to being supercooled the water freezes again upon impact.
Hail: Precipitation composed of chunks or lumps of ice formed in strong updrafts in
cumulonimbus clouds. Individual lumps are called hailstones. Most hailstones are spherical or oblong, some
are conical, and some are bumpy and irregular.
Snowflake:
Formed when water vapor turns to ice crystals either in the clouds or on the way down to Earth.
Winter Storm Watch: Issued under changing weather
conditions, when the specific timing, location, and path of an approaching or forming storm are
undetermined.
Winter Storm Warning: Issued when more than 6
inches of snow, a significant ice accumulations, or a dangerous wind chill (or any combination of the
three) is expected within 24 hours.
Blizzard Warning:
Issued when sustained winds of 35 miles per hour or greater, in combination with considerable snowfall and
poor visibility is expected for three hours or more.
Northeaster (aka Nor'easter):
A storm that typically produces heavy snow and rain and generates large waves in the Atlantic costal
regions, often causing beach erosion and structural damage to buildings. Wind gusts can exceed hurricane
speeds. |
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The best place for getting snow, IMHO, is on the front range of the Rocky Mountains in Colorado. We lived
both in Colorado Springs and in Loveland (just south of Ft. Collins), and the nice thing about snow there is that
a foot of it will fall one day, and it will all be gone three days later. Due to the arid environment and high
altitude (a mile+) the melting snow would evaporate immediately and not generate the muddy mess that you get in
the northeast. Additionally, the thin air creates the right condition for sublimation whereby the snow passes
directly from the frozen state to the gaseous state without passing through the liquid state. Again, no muddy
mess.
| Hail Classifications |
| H0 |
Pea size, causes no damage |
| H1 |
Leaves and flower petals punctured and torn |
| H2 |
Leaves stripped form trees and plants |
| H3 |
Panes of glass broken, auto bodies dented |
| H4 |
Some house windows broken, small tree branches broken, birds killed |
| H5 |
Many house windows broken, small animals injured, large tree branches broken |
| H6 |
Roof shingles destroyed, metal roofs dented, wood window frames broken away |
| H7 |
Roofs shattered, autos seriously damaged |
| H8 |
Roofs totally destroyed, small tree trunks split, people seriously injured |
| H9 |
Concrete roofs breeched, large tree trunks split/knocked down, people at risk of fatal injuries |
| H10 |
Brick structures damaged, people killed |
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Kirt
Blattenberger… single-handedly redefining what an engineering website should be.
Carpe Diem!