From his bedroom in Phoenix, Bill Ryerson sees what the federal government's costly satellites cannot.
Aided by three rather inconspicuous devices on the roof of his house, the 17-year-old Dulaney High School senior tracks local weather conditions as a "spotter" for the National Weather Service's Skywarn program.
About 300 spotters are scattered around the Baltimore area, with 1,500 in a region that includes Washington and parts of Virginia and West Virginia.
The weather service's regional office in Sterling, Va., relies on their input for everything from routine temperature and precipitation readings to reports of harsh weather phenomena such as thunderstorms, tornadoes, floods, high winds and snowstorms.
"We're not going to find out about severe weather without spotters," said John F. Newkirk, a weather service program manager.
"If we didn't have spotters out there reporting for us, then we couldn't report as accurately," he said.
Sophisticated equipment such as satellites and Doppler radar is good for getting the big picture, weather service officials say. But the volunteer spotters are necessary to add details that sharpen that picture locally.
"The NWS is in Sterling and they can't see a creek flooding in Baltimore County. We give them eyes around the state to see what's going on. And then they can pass it along to the public, so people can take precautions," said Bryan Slattery, 30, a spotter and service manager at a Towson computer store.
Ryerson said his interest in spotting began as a competition with the newspaper.
"About three years ago I found myself reading the weather page every day, and without knowing a lot about the weather I was making my own forecasts," he said, explaining how his fascination with knowing the difference between a hygrometer and an anemometer started. (Hygrometers measure humidity; anemometers measure wind speed and direction.)
During the past three years, he has gone from reading the weather page to contributing to it.
Ryerson said he has spent about $1,000 to assemble the weather station that tracks conditions from the roof of his house.
Readings are made every 30 minutes, transmitted through wire into a small, digital recorder on a desk in his modestly furnished room, and stored in the device's memory.
Later, when he needs the information, he downloads it into a computer downstairs, where he has maintained records of the past 30 months' weather.
Every morning about 7 -- although he acknowledges weekends are iffy -- he calls in his readings to the National Weather Service.
Spotters vary as much as snowflakes.
According to the weather service, the minimum age is 14, but some are well into retirement age. They include farmers, lawyers, homemakers, firefighters and television camera operators. Most are ham radio operators.
All that's required to become a spotter is a keen eye.
"They don't have to be scientists. All they have to do is tell us what they see," said Melanie Hall, director of Skywarn, the weather service's national network of weather-spotter volunteers.
The weather service encourages prospective Skywarn volunteers to attend its three-hour class where they learn to recognize severe thunderstorms, tornadoes, wind damage and types of precipitation.
No special equipment is required, though many people tend to have a few basic instruments, such as thermometers, barometers and rain gauges, Hall said.
Many simply are weather addicts and want to know as much as possible.
"I'm a guy who wants to know a little bit more than the temperature outside," Slattery said. He said his wife was shocked seven years ago when he spent $1,500 on a weather station and additional equipment without really having a reason.
"She thought I was nuts," he said, "but afterward she just got used to having all that information."
Slattery, who lives north of Jarrettsville in Street, acknowledges he's a bit of a frustrated weatherman and said his secret fantasy is to be a storm chaser like the characters in the movie "Twister."
For now, though, he'll stick to reporting.
Another spotter, Joe Elliott, 55, of Riviera Beach, said spotting became his hobby because he was fascinated by nature.
"It's awesome. It's something man can't control. I was mystified by storms and their strength," Elliott said.
Ryerson hopes to turn his hobby into a career. He said he plans to major in meteorology in the fall when he heads to Pennsylvania State University, which he hopes will be the first step in a lifetime of analyzing weather.
"I'm sure my knowledge will triple," said Ryerson, who still tries to match forecasting wits with the professionals. "I'm pretty psyched to learn about it next year."
Pub Date: 4/24/97