Saturday marked the first day of fall and, although it's not quite sweater-weather season in Texas, seasonal allergies have already hit Texans hard.
That could be due to the current high ragweed count in the Dallas-Fort Worth area — which is typical for this time of year. North Texas allergists and immunologists like Dr. Sheeba Cherian say they've already seen an increase in patients coming in with itchy ears, watery eyes and runny noses.
"The thing about North Texas is that we're overall a very warm climate, we don't get a lot of frost" she said. "So anytime we live in a climate where there is not snow or a big frost each year, we kind of have a year-round pollen season."
There are three notable pollen seasons in Texas: Ragweed and elm in the fall, cedar in the winter and all other tree pollen in the spring until around June.
A frost could bring an end to ragweed pollen this fall, but the National Weather Service forecasts unseasonably warm weather continuing into October. And despite a winter storm earlier this year, there have been days with temperatures in the 80s and 90s since January, according to past climate records logged by the National Weather Service.
“Sometimes when the summer heat comes along, things bloom quickly and then it stays up in the air for longer periods of time,” Cherian said. “Warmer temperatures also change the seasonality of pollen. So, whenever we kind of move towards warmer climates, certain trees and leaves can pollinate sooner in the year.”
Cedar is a type of pollen that contributes to what Texas A&M Forest Service calls a bonus allergy season.
While cedar trees are more common in Central Texas, wind can bring cedar pollen to North Texas from December to February.
“In lots of other places across the U.S., you just have your fall and your spring tree allergies, but it’s that December through February timeframe that makes cedar fever unique,” said Alison Baylis, Texas A&M Forest Service regional urban ecologist.
As far as the pollen outlook for this year, Baylis said its hard to give a definite answer. While warmer weather can mean trees pollinate sooner, other factors impact pollen counts per season.
As of Wednesday, North Texas is under extreme drought conditions with exceptional drought impacting Central Texas and parts of East Texas and the Gulf Coast. Drought in areas like North Texas can stress trees and make them less likely to produce as much pollen as a healthy tree, Baylis said.
“In times of drought, you can think of it that trees essentially can’t feed themselves,” she said. “One way that could impact pollen is that there would be less resources to put into pollen production.”
Even if a tree produces less pollen than usual, there are still other factors that could play into the intensity of allergy season.
Trees could produce less pollen one year, but windy conditions kicking up pollen in the air could make it seem no different from other seasons. By contrast, if trees produce more pollen but consistent rainy conditions keep pollen out of the air, the allergy season could be less intense.
“There’s just all these different variables that go into the equation and there’s really no way for me to say for sure which one is the real culprit,” Baylis said.
