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Wind chill warms up a bit Weather service's new chart more accurately reflects the feeling on skin By MELISSA MARTIN Medford meteorologist Jim Reynolds remembers coming down the mountain after a night of skiing in the Midwest. When his friends dropped him off at his car, he tried to start the engine. "I had a hole in my glove and was resting my thumb on the ignition," Reynolds said. "It was so cold, I had to crank on the car for 10 to 15 minutes before it would start." The next day, he discovered frostbite on the exposed skin that touched the car's cold metal. He was fortunate - there was no permanent damage. Reynolds learned first-hand how fast skin tissue can freeze when the air is cold enough or the winds strong enough. But a new wind chill chart that the National Weather Service will begin using in November documents conditions in which frostbite can occur within 15 minutes. "This new chart more accurately reflects the impact of cold and wind on the human body," said Reynolds, a meteorologist with the National Weather Service in Medford. Scientists created the new chart using results from clinical tests in a wind tunnel at the Defense and Civil Institute of Environmental Medicine in Toronto, Canada, said Mark Tew, a program manager for the National Weather Service in Silver Spring, Md. "People volunteered to go inside a chilled wind tunnel," Tew said. "(Researchers) measured the drop in skin temperature on their faces at various wind speeds and air temperatures." The research helped scientists conclude that at a wind-chill temperature of 19 degrees below zero, frostbite can occur in 15 minutes (assuming an air temperature of 5 degrees Fahrenheit and wind speeds of 30 mph). "This brought the new index into the 21st century," Tew said. Meteorologists since 1945 used an index based on simple research methods - measuring wind's impact on a water-filled plastic jug hanging from a pole. The new index uses advances in technology, science and computer modeling, Tew said. It's also a facial model; it assumes that the most exposed part of the body tends to be the face, which on average is 5 feet above the ground. The old index used 33 feet, the standard wind gauge height. So when Mount Ashland skiers read wind-chill temperatures posted at two lift sites on the season's coldest days Sonnet and Aerial chair lifts, they might see higher numbers than were posted in identical conditions last year. "With lower wind speeds, 10 mph or less, you won't see much difference," Tew said. "But once you get 20-mph winds, the new wind chill is warmer than the old." A new wind chill chart won't change the advice Bruce Meek gives skiers. The Mount Ashland manager tells his chair lift operators to warn skiers who have exposed ears, noses and cheeks to bundle up, especially the 2,600 youngsters who participate in school ski programs each winter. "Frostbite is the freezing of the fluid in the cells," Meek said. "When they burst, it destroys tissue." First the skin turns red, which is frost nip, he said. "Then it goes into frostbite and the skin turns white or gray and has a waxy look to it," Meek said. "In advanced stages, it can turn black." He's never seen an extreme case that required amputation during his 27 years on Mount Ashland. But he hears of a couple of minor frostbite cases a year, mostly on the top of the ear, the tip of the nose, cheeks, fingers or toes. Another group that pays attention to wind chill temperature is Jackson County Search and Rescue members. They use weather information when they create action plans for finding lost victims, said Keith Stockebrand, vice president of the Prospect unit. "What the winds do is a factor," said Stockebrand, who sees one or two frostbite cases a year, mostly among hunters. "It depends on their clothing, whether their skin is exposed, how high the elevation and whether it's snowing or clear." The new wind chill chart will become part of winter forecasts used at Crater Lake National Park, where about 100 people a month ski, snowshoe or camp on 200,000 acres of back country, including the 35-mile, snow-packed rim road. Temperatures at Crater Lake are usually mild, averaging in the 20s and 30s in the daytime and dropping to the teens at night, said Dan Jacobs, back country district manager. But Crater Lake weather can turn extreme at a moment's notice. "Winds can come up any place above the timber line on the rim," Jacobs said. "You can have dead calm one day and howling hurricane winds the next. It's a pretty unforgiving environment up here in the wintertime." While meteorologists in the United States and Canada will begin using the new wind chill chart in November, the rest of the world will not. The National Weather Service presented the information to the International Society of Biometeorology in Freiburg, Germany, in June, Tew said. But the society chose to wait for a universal temperature index that may take several years to develop. "We're ahead of the rest of the world," Tew said. Reach reporter Melissa Martin at 776-4497, or e-mail [email protected] The last big chill The most recent hard freeze in Medford that caused pipes to freeze and sent folks outside for repairs occurred on Dec. 21-22, 1998, when temperatures dropped to 6 degrees Fahrenheit. People can prevent frostbite by keeping skin covered with gloves, neoprene masks, synthetic scarves and hats and by taking a break from work or play to warm up indoors or by a fire. 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