The National Weather Service hopes to put you on the map … sort of. Volunteers are needed for the Community Collaborative Rain, Hail and Snow Network (CoCoRaHS). The program, which expanded to Alabama on Nov. 1, will help meteorologists and researchers study the variability of precipitation across southwest Alabama.

Data from each volunteer’s backyard rain gauge will be recorded and compared to radar totals. The information will ultimately be placed on maps that are posted on the Internet.

Gary Beeler, warning coordination meteorologist with the NWS office in Mobile, said CoCoRaHS was organized in 1998 in Fort Collins, Colo. after a flood devastated many homes and businesses in the area. When rain totals were checked afterward, it was determined no precipitation had reached official weather service gauges.

The volunteer effort is meant to fill in the blanks between the NWS weather stations by blanketing the area with weather watchers who are willing to place a manual 4-inch diameter rain gauge in their yard and report the daily totals online. The durable plastic gauges sell for around $25.

“They hold about 11 inches,” he said. “That’s important here.”

Beeler, who coordinates the program locally with fellow meteorologist Jack Cullen, said, “They did testing on the different rain gauges and found these to be the most accurate. They want everybody to be the same so they’re asking them all to measure with the same type of equipment.”

According to the research, the majority of automated rain gauges reported less precipitation than actually fell by a significant amount — sometimes 25 percent or more over several months of testing. The manual gauges are preferred because researchers are interested in observing and understanding natural precipitation variability as accurately as possible.

Beeler said gauge placement is just as important. It needs to be placed in an open area, away from trees and rooftops.

“You don’t have to be a meteorologist or anything,” he said. “Farmers probably have rain gauges on all the farms in Baldwin County.”

Radar indicated a recent storm dumped nearly 20 inches of rain on Pensacola, Beeler said, adding data collected through the CoCoRaHS network will enable NWS to confirm such totals in the future.

“It does have some real use,” he said. “It makes it into our data and helps our forecasts.”

Florida is also part of the program, Beeler said, and Mississippi will join in August. CoCoRaHS now has more than 6,500 registered observers in 26 states.

You can visit www.cocorahs.org to learn more about the program, find out where to purchase a rain gauge and register your backyard (or schoolyard) as an official reporting site.

You may also view the maps there and see data from observation posts across the country.

NWS officials encourage participants to take the online training located on the CoCoRaHS Web site that will illustrate proper rain gauge setup and reading procedures, along with needed program instruction.

Those who have other types of gear for collecting meteorological data can help as well. Beeler said, “If anybody has wind equipment and they record any above normal wind speed, we want to have it.”

If you have additional questions about CoCoRaHS, call Gary Beeler or Jack Cullen at (251) 633-6443.