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One of the goals of NeRAIN is to study hailstorm characteristics;
the location, time, size, quantity and hardness of hailstones. In
a hailstorm, the size and quantity of hailstones can vary quickly
and over very small distances, like one mile or even just across
the street. We need your help in determining when hail begins, how
long it lasts, what size and type of stones, and whether or not
rain has accompanied the storm.
Even in Nebraska where hail storms are common there will still only be a few hail-producing
storms each year. What this means is that you have to be ready in
advance so the hail doesn't catch you by surprise.
Follow these steps in reporting hailstorm information.
Step 1. If you are at home (or at the site of your reporting
station) when a hailstorm hits, note the time that the hail begins
as accurately as possible. The times that hail begins and ends are
very important pieces of information needed by scientists. If you
feel it is safe, report the onset of this storm by phone or internet
using the Quick Hail Report format.
If you do not feel it
is safe to be on the phone or computer due to nearby lightning,
wait until the storm passes.
Step 2. Observe the hail storm in progress from a safe and
secure location. Please take notes during the storm to help
you remember important features from the storm, such as changes
in stone size, hardness, and sudden changes in the number of stones
reaching the ground. Do not expose yourself to dangerous
hailstones. Keep a ruler handy. When a break in the storm gives
you the opportunity, measure the diameter of the largest,
the smallest and the most common sized hailstones. If you do not
have a ruler, use your pocket change. The diameter of a dime is
slightly less than 3/4 inch while a penny is almost precisely 3/4
inch across. The diameter of a nickel is slightly more than 3/4
inch while a quarter is slightly less than one inch across. Also
check to see if the hail is clear, white, hard, soft, smooth, rough
or has any other interesting properties. Take note if the hail began
before, after, or at the same time that rain began.
Step 3. When the storm has ended, try to approximate the
number of stones per unit area (per square foot) which hit the ground.
Since the number is sometimes very large, it may be easier to record
the average distance between stones on the ground. If large quantities
of hail fell, measure the average depth of accumulated hail on the
ground. At the same time, do a quick assessment of hail damage.
Most storms do very little damage except to tender plants.
Step 4. Fill out the NeRAIN Hail
Report information site. Be sure to include your station name and number.
If you were not at home, but you experienced hail at another location,
a hail report is still beneficial. Make sure, however, to record
your actual location accurately so the report is not accidentally
associated with your normal station location.
Step 5. Submit a
"Detailed Hail Report" by computer.
Things to Remember: When measuring hail.
- Note and record the time when hail begins and ends as accurately
as possible.
- Do not get in the path of falling hail stones.
- Hail storms come on fast and furiously. Be ready.
- Two types of hail reports are encouraged:
- Promptly notify us when hail begins at your location to
give us a "heads up" on developing or approaching
storms. (Quick Hail Report
Form)
- Submit by telephone or internet a detailed summary of hail
at the end of each storm using the reporting formats provided.
(Detailed Hail Report Form)
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What if a hail storm occurred, but you were not at home
to observe it?
If this happens, and it will, you will not be able to provide
detailed information about the storm. If you can approximate
when the storm occurred and some characteristics of the storm,
try to do so. When you submit your report, make appropriate
remarks expressing your uncertainty. If you do not know the
time of occurrence, but you do know the date, that is also useful.
Turn in the hail pad with an incomplete hail report card and
a note saying, "Sorry, I wasn't home at the time of the
storm."
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What if you observer a hailstorm from a different location
than your station?
If you are not at home but experience hail storms somewhere
else, we welcome these reports as well. Always make sure you
note the time and location as accurately as possible. Do not
give your station number if you are reporting from a different
location. That might confuse us.
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What if you see some giant hailstones that are more than
2.5 inches in diameter or have very interesting shapes, sizes
or other characteristics?
Every year, giant hailstones fall somewhere in Nebraska.
Fortunately, at any specific location they are quite rare. If
you see very large or very unusual hail stones, take close-up
photographs, collect some samples, preserve them in your freezer,
and contact your NeRAIN coordinator. If you see intact hail
stones in excess of 5 inches in diameter, quickly and carefully
wrap and freeze these stones. These are very rare and will be
of great interest to scientists (and the media).
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