Rain or Shine, Volunteers Are Left to Their Devices

Rain or shine, each afternoon at 3:30, 365 days a year, the phones start ringing off the hook at the National Weather Service office at Lindbergh Field.

The first call might be from the fire station in Chula Vista, followed by the Harbor Patrol in Oceanside, and then perhaps by the park ranger at the San Diego Wild Animal Park east of Escondido.

By 5 p.m., all 26 stations of the countywide volunteer weather network will have reported the high and low temperatures, and precipitation in their areas. Armed with that data, chief meteorologist Wilbur Shigehara and his colleagues will be well on their way to compiling the overall picture of county weather for the day.

For almost a century, the weather service in San Diego, as well as throughout the nation, has relied on a far-flung network of unpaid observers to provide critical measurements, without which the official forecasts would be far more difficult.

Because Shigehara follows in the traditions of U.S. meteorologists who are sticklers for accuracy, he wants the daily highs and lows to be measured according to national standards, unlike the flashing neon temperature signs on banks and shopping center marquees.

“When someone says that the temperature was 81 degrees, we don’t want anyone to come back at us later and say, ‘Well, how do you know that it really was 81, and not 84 or 79 or somewhere in between?’ ” Shigehara said.

At Shigehara’s office, there are devices that do nothing but check the accuracy of other devices. The electronic probes positioned near the active Lindbergh Field runway--to provide pilots with data as close to runway conditions as possible--are backed up by additional instruments on the roof of the weather service building.

The weather service supplies the thermometers and rain gauges to members of the network--and periodically checks them for accuracy. While the network stations are far simpler than the one at

Lindbergh Field, Shigehara is instituting an annual review so his volunteers can attain official status.

“They technically have been unofficial, but we feel that any time the National Weather Service puts out temperatures to the public, they should be certified as official, in that we should be able to defend them against any questions later,” he said. “We want to make sure that everyone does things with the same methods, at the same time.”

For example, temperature devices should not be out in the open and exposed to the sun. They should be maintained in a ventilated white-painted box or container that is 5 to 5 1/2 feet above the ground. Whether old-fashioned thermometers or the latest electronic probe devices, they must face north so that no sun shines directly on them when a container is opened for maintenance.

Rain gauges must be in an open area, with no trees, ledges or eaves hampering the collection of raindrops.

“We talk about all of this to our volunteers now and install the equipment at sites,” Shigehara said. “There are a lot of factors involved. You can’t have a thermometer nailed to a wall since you’d end up measuring building heat as well as air temperature.

“But without inspecting each site for maintenance and exposure annually, we don’t know for sure that everything is in order. Someone may inadvertently put the exhaust from an air conditioner next to a thermometer.”

Shigehara tries to make the work as simple as possible for his volunteers. Although he would like to have readings at least twice a day from them, he settles for a minimum once-a-day reporting.

“All we ask is that everyone report once a day, taking no weekends off, no Christmas or other holidays, no vacation, and do it without pay,” Shigehara said.

For that reason, most of the outlying weather locations today sit at fire stations or other government agencies where someone is around 24 hours a day, every day. Many of the observers not only provide daily temperature and rainfall data for public use but also contribute written records on a monthly basis for national weather archives to serve as raw material for climate historians in future years.

In addition, some observers, such as Archie and Gwen Leach in Campo, serve as aviation reporting stations as well, compiling wind and barometer readings every two hours so pilots can be continually updated. Several stations, including the Poway and Santee fire departments, send moisture data in to a nationwide fire danger index network operated by the U.S. Bureau of Land Management. At Cabrillo National Monument and Oceanside Harbor, the observers take marine readings for boaters.

“I can’t think of a single observer today not connected with a government agency who is not” retired, said Carl Freeman, who manages the annual inspection program for more than 300 stations throughout Southern California that also keep the monthly written records.

“The old-time ethics have changed; people don’t want to do anything for nothing anymore, especially if they have to do it every day.”

Even at many government locations, Freeman has installed low-maintenance electronic devices to minimize the work involved in recording data.

At the Chula Vista fire station on F Street, firefighter Mike Kirby now has only to press a button on a digital readout inside the business office to get the daily readings. The digital box is wired to an electronic temperature probe outside the building.

“It’s a lot easier than before, when we had minimum and maximum temperatures to read,” Kirby said.

Training Officer Sam Lopez added: “When we had the old type, it was easy to make errors if someone didn’t reset the thermometers properly. You could get the same high temperature day after day.”

The number of volunteer stations is determined from a grid overlaid on a map of San Diego County.

“We want enough stations to adequately represent county weather,” Shigehara said. “We don’t want them too far or too close to each other.” In addition, the weather service does not place new stations in developing areas until it can determine a logical central location.

“For that reason, we do not have one in Rancho Penasquitos or in Mira Mesa yet, since they are still somewhat (growing) areas,” Shigehara said. “We do have a fire station in Poway, near Penasquitos.

“Normally, we get a request or an outcry from a community or chamber of commerce. We’ll check out the need and then look for a fire station or individual willing to take on the job. A lot of cities like to see their names in print.

“After all, there really is a lot of public interest in the weather.”