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How
Do You Measure Snowfall? The tried and true method (and the one used
by the National Weather Service) to measure snowfall is to measure the depth of
snow using a hand-held, calibrated instrument commonly called a ruler. There are
a couple of rules that you need to follow. Because snow melts or can be blown
around, measure the snowfall in an odd number of areas and take the average. This
helps to give a better idea of the amount of snow that fell. You will also want
to remember that snow falls on top of grass leaving pockets of air between blades
so that the snow does not actually reach the ground. Inserting the ruler to ground
level will give you an exaggerated snowfall measurement if there is a lot of grass
at the location. For a better assessment of snowfall
amounts, a snowboard is a great tool. Not the kind you schuss down the slopes
on but one you can easily construct at home or in your classroom.
Building a Snowboard 1) Take a wooden
board about 18 inches wide and 2 feet long. Paint the board with several coats
of high gloss light (white is preferable) colored paint so that it is very smooth
and shiny.
2) Place the "snowboard" flat on the ground in an area
away from buildings and trees where snow is most likely to accumulate.
3)
Be sure to mark its location with something that rises above the ground several
inches so that you can find it in deep snow - like a small flag.
4) During
a snowfall event, use a ruler to measure the amount of snow in inches or centimeters
that has accumulated on the "snowboard".
5) Then remove that accumulated
snow and start over again (just brush it off). Repeat this process every hour
during the snow event. You will have hourly snow readings and a relatively accurate
cumulative reading for the event. This can be
a great activity for those of us who live where it snows and can get outdoors.
The next step is to determine how much liquid precipitation the snow represents.
It makes a great math lesson. Every hour that you record snow accumulation, you
should also record the outdoor temperature and notes about the change in temperature
during the previous hour. Then use the table below to determine the amount of
water in the snow that fell for each hour. You can then calculate the approximate
liquid precipitation per hour, total for the time period measured and also the
average hourly precipitation during the day. It makes practicing math skills like
addition and division a lot more fun! If you cannot construct a snowboard, wooden
decks or platforms and grassy surfaces will still be good choices. Have fun and
let us know how your "snowboarding" works. | 
