Dr. Jamison explained: "If you spend two weeks in Florida sipping pina coladas, you may feel a lot less pain than you did shoveling snow at home in Boston. But if you move to Florida and your body gets used to that warm climate, when the temperature drops you may hurt just as much as you did when the weather changed in Boston."

Thus a spell of wet weather in normally dry San Diego might be more disruptive to pain sufferers than the year-round dampness of Nashville, whose residents become accustomed to wet conditions. Such a finding counters the common notion that warm, dry climates are best for people in pain.

The researchers were also surprised to find that younger patients -- the survey involved people 18 to 85 years old -- reported the greatest sensitivity to weather changes. Patients with arthritis were also highly sensitive.

The researchers conducted the four-city survey to examine more closely the longstanding belief that patients with chronic pain -- arthritis, headache, backache and the like -- are sensitive to weather changes and can often predict those changes as much as a day ahead based on an increase in pain. The researchers sought to determine if weather-induced changes in pain sensitivity varied with climate. They especially looked at whether those who live in cold, damp climates suffer the worst weather-related effects, and what characteristics define patients who are most sensitive to weather changes.

Although the survey showed, as pain patients know all too well, that cold, damp weather is perceived to have the greatest effect on pain, pain is more likely to be affected by a change to cold, damp weather than a steady climate of it. Two-thirds of the patients said weather changes affected their pain, and of those, slightly more than half said their pain was affected even before the weather changed.