With South Florida's rainy season approaching, many people will be able to predict storms almost before the weather service does. They'll feel it in their bones.
Local doctors say it's not an old wives' tale. When barometric pressure changes, those with arthritis, sports injuries or hip, shoulder or knee replacements commonly feel an ache.
Dr. Paul Meli, an orthopedic surgeon based in Fort Lauderdale, injured his shoulder water-skiing about 30 years ago. When it stiffens up, he knows rain is coming. "It definitely gets sore and stiff on a lousy day," he said.
Why can bones feel rain? According to doctors, most bones are covered by a thin layer of tissue containing nerve endings. When barometric pressure falls, sometimes an indication that rain is approaching, the bones ever so slightly expand, stretching that layer and causing pain.
Because teeth don't have this layer of nerves, they usually don't ache when weather changes. However, softer tissues of the body also expand and contract with changes in pressure, which is why scars and sports injuries unrelated to bones also can hurt, said Dr. Nabil El Sanadi, chief of emergency medicine for Broward Health System.
Other conditions, such as migraines, sinus headaches and some nerve disorders, also can be predictors of rain. Some people can smell the increase in humidity in the air before rain. And some can sense the temperature is going to plunge because their hands and feet get cold -- the result of slowed-down circulation, El Sanadi said.
"Sudden changes in temperature or pressure actually magnifies discomfort," he added.
Meli, who specializes in hip, knee and shoulder replacements, said many of his patients can predict rain after having a half-pound of metal surgically implanted in their bodies. "The metal conducts cold more than the tissues of the human body," he said. "People come here all the time and tell me it's going to rain."
El Sanadi, who had surgery on his right knee, said changes in pressure, temperature and humidity -- all precursors of a good downpour -- cause him discomfort.
"I can't always predict what the weather will be, but I can tell you when it's cold or humid outside before I get out of bed," he said.
Robin Terrill, a weather spotter who is trained to anticipate severe storms and tornadoes, said he had both his shoulder rotator cuffs repaired, a couple of lower-back surgeries and a broken tibia in his right leg.
"The weather plays an important role on how I feel," said Terrill, 61, of Fort Lauderdale. "When my shoulders click, I know that it is going to rain."
Maurice Dake, of Lantana, another spotter, said he can't predict atmospheric changes by way of his bones. But he said animals can sometimes anticipate earthquakes.
"You'll see barnyard animals running around in circles and doing strange things just before an earthquake," he said. "It probably has to do with change in barometric pressure."
The Farmer's Almanac concurs that people can feel rain in their bones. It says since the 1960s, medical researchers have found a "genuine connection" between increased pain and cold, wet weather.
"While the effect is most commonly linked to arthritis sufferers, many have also reported feeling increased pain from nerve disorders, recently healed fractures, migraines, toothaches, corns, and even scars, when the weather was about to change," according to this year's edition.
Timothy E. O'Connor, spokesman for the Palm Beach County Health Department, said he's skeptical that people can predict rain based on their medical conditions. And he has an arthritic knee.
"It doesn't predict for me. It tells me what I shouldn't have done, like over-dancing at a wedding on St. Patrick's Day," he said. "I can't do the jig like I used to."
On the other hand, he said, "barometric pressure changes during a high tide and full moon definitely affect pregnant women. A lot of hospitals see early deliveries during that time."
Forecasters at the National Weather Service in Miami have an arsenal of high-tech tools, such as radar, satellites and computer models to develop official forecasts. Do some of them rely on their innards to augment their predictions?
"Not that I know of," said meteorologist Robert Molleda. "But it's possible it plays an intangible role."