A late freeze put a snowy exclamation point on a fairly mild winter for much of the United States, and experts say it's hard to predict what this weird weather means for allergy sufferers.
It's certain allergy season is on its way, though, bringing sneezing, wheezing, coughing, runny noses, itchy eyes and headaches with it.
The allergy season is really several seasons. Trees start scattering their pollen in early spring, followed by grasses, and then ragweed kicks in during the summer and runs through fall.
Then there's mold, which can be a year-round problem.
But making allergy season really unpredictable is the role of weather, said Mike Tringale with the Asthma and Allergy Foundation of America.
"It's a hard call to make," he said. "It's not just pollination, but what the wind and the rains and the other weather patterns do to that pollen; whether it washes it away or blows it 500 miles to the next town or city is a very difficult thing to project."
Dr. Charles Feldman, an allergist with Columbia University's Department of Pediatrics, said he had an unusually large number of patients complain about hay fever over the winter.
"There were people complaining this winter of itchy, watery eyes, which is something you don't see until April or May," Feldman said.
Feldman said complaints dropped after the January freeze that blanketed the New York City area with snow and ice.
"Things become very dormant with the cold weather," he said. The cold snap could either delay the start of the allergy season, or give it a head start, depending on how close the trees are to releasing pollen.
Dr. Jeffrey Adelglass measures the pollen count for the Dallas, Texas, area. He said unseasonably warm temperatures led to relatively high levels of cedar and elm pollen.
Taking medications before the pollen onslaught can help people get ready for the allergy season, Tringale said. Other preventive measures don't involve drugs.
"If you have a choice to plan an outdoor event versus an indoor event, people with spring allergies, who have tree pollen allergies, would be better off choosing indoor activities during the peak pollen season," he said.
About 18.6 million adults and 6.7 million children have hay fever, according to 2004 reports by the National Center for Health Statistics.
An allergic reaction happens when the body identifies a normally harmless substance such as pollen as an invading germ. The immune system produces histamine to fight off the intruder and that chemical causes the symptoms that make people miserable.
Antihistamines and other treatments can reduce the symptoms -- but there is no cure.