Charles Kuster
EF4
I asked this question several years ago, but the network has exploded since then, so has anyone heard of CoCoRaHS (Community Collaborative Rain Hail and Snow Network)? The project consists of over 10,000 volunteers spread over 40 states. Volunteers essentially take precipitation (generally rain or snow) readings every morning and then report them online to a national data base. Here is the link to the home page: http://www.cocorahs.org/
I have been a county coordinator for almost seven years and now I am analyzing hail data (which is by far my favorite aspect of CoCoRaHS) while studying at Colorado State. The analyzing process consists of counting the dents, determining max, min, and average size, classifying the hail has hard or soft, determining severity of wind at the time of the event, measuring average distance between dents, and picturing the hail pad. I have analyzed about 330 hail pads so far and have noticed a few general trends:
1. It is extremely rare for a hail event not to have small hail (1/8†in diameter). I have only come across a couple cases in which the minimum hail size was not “rice†(1/8â€).
2. The most common average size for a hail event is ¼â€.
3. The most common wind classification for a hail event is “light†which includes hail falling at an angle of 10-20 degrees.
4. Most hail that falls has a hard consistency. I do run into many cases in which the consistency classification is “mixed†but a majority of the hail that falls is hard.
5. The average number of impact dents over the one square foot hail pad is approximately 750, but there is a huge range. Some events contain a mere 25 dents while others may have over 4000 (not fun to count!
)
It is important to note that about 90 percent of the cases I have seen so far have come out of Colorado.
Here are some examples of hail pads:
Tennis ball size hail
1 ½†hail
Nickel size hail
Pea size hail
Here is a date of interest: 5/22/08 Windsor tornado day
Much more data can be found be serching through the "View Data" section on the home page. Enjoy!
I have been a county coordinator for almost seven years and now I am analyzing hail data (which is by far my favorite aspect of CoCoRaHS) while studying at Colorado State. The analyzing process consists of counting the dents, determining max, min, and average size, classifying the hail has hard or soft, determining severity of wind at the time of the event, measuring average distance between dents, and picturing the hail pad. I have analyzed about 330 hail pads so far and have noticed a few general trends:
1. It is extremely rare for a hail event not to have small hail (1/8†in diameter). I have only come across a couple cases in which the minimum hail size was not “rice†(1/8â€).
2. The most common average size for a hail event is ¼â€.
3. The most common wind classification for a hail event is “light†which includes hail falling at an angle of 10-20 degrees.
4. Most hail that falls has a hard consistency. I do run into many cases in which the consistency classification is “mixed†but a majority of the hail that falls is hard.
5. The average number of impact dents over the one square foot hail pad is approximately 750, but there is a huge range. Some events contain a mere 25 dents while others may have over 4000 (not fun to count!
)It is important to note that about 90 percent of the cases I have seen so far have come out of Colorado.
Here are some examples of hail pads:
Tennis ball size hail
1 ½†hail
Nickel size hail
Pea size hail
Here is a date of interest: 5/22/08 Windsor tornado day
Much more data can be found be serching through the "View Data" section on the home page. Enjoy!
