Allergy

Allergy Season Grows At Least 3 Weeks Longer Across Much Of US, And It May Be Longer Where You Live

Over the past 50 years, the number of days between the last freeze of spring and the first freeze of fall has surged. That means extended suffering for seasonal allergy sufferers across the U.S.

How Much Longer Is Allergy Season In Your Area?

Allergy season has grown longer and stronger across most of the U.S. by an average of about three weeks since the 1970s, according to a newly released study from Climate Central.

The center's researchers found that 173 major cities got an extra 21 freeze-free days, giving plants more time to bloom and release the pollen that makes so many of us miserable.

About one in four adults and one in five children suffer from seasonal allergies, says the CDC.

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Some regions and cities are seeing even more days above freezing, so if it feels like allergy season is starting earlier for you, it may not all be in your (congested) head.

(MORE: Spring Allergies Can Mess With Your Skin)

While all climate regions have seen their freeze-free season lengthen, the Northwest is leading that trend, with 31 more days. Allergy sufferers there now endure about 187 days of pollen between the first and last freeze of the year.

So is the seasonal part of seasonal allergies becoming a thing of the past?

The growing season lengthened the most in Reno, Nevada, by 100 more days. Across the map to the South — Tupelo, Mississippi, and Myrtle Beach, South Carolina, are both seeing 51 extra days of allergy season.

This year, despite a record-breaking East Coast blizzard, the first leaves of spring were seen in early January in parts of Texas, Louisiana, Mississippi and Alabama. Spring blooms are also arriving two to three weeks early in parts of Colorado, Kansas and Missouri.

(MORE: America’s Hottest Winter Temperature Just Happened)

Climate Central blames warming temperatures and heat-trapping pollution for the earlier springs and longer allergy seasons.

Researchers have found that higher levels of carbon dioxide can increase pollen production, and one study predicts that we’ll be facing a 200% increase in pollen production by the end of the century.

So what can you do to cope?

Clouds of yellow-green pollen of pines and firs transported in air vortices for the usual spring pollination — Clouds of yellow-green pollen of pines and firs fills the air during spring.
(Getty Images/GitoTrevisan)

Symptoms Season

The calendar may not say spring, but your nose will know, so you may experience symptoms earlier or later than usual. So meet with your allergist or start your regimen early.

(MORE: How To Really Get Relief From Nasal Spray)

Limit Time Outdoors

Keep up with air quality reports in your area. You can use our daily allergy forecasts at weather.com and on our app. If pollen is high in your area, consider spending less time outdoors.

Protect The Indoors

Close windows and doors to minimize pollen in your home. Change clothes and shower when you arrive home to avoid tracking pollen all over your house. Use HEPA filters to clean the air.