The worst cities for allergy sufferers are usually found in the Southeast, but the new list just released by The Asthma and Allergy Foundation of America shows a surprising shift to the West in 2026.
More than a quarter of adultsin the U.S. suffer from seasonal allergies, according to the Centers for Disease Control and Prevention. New research also shows that allergy season hasgrown longer and strongerin almost every part of the country.
(MORE:How To Really Get Relief From Nasal Spray)
For its report, The Asthma and Allergy Foundation scored cities not just on the amount of tree, weed and grass pollen, but also on how much over-the-counter allergy medicine is being bought. It also looked at how many board-certified allergists and immunologists are available to help treat a city's allergy sufferers.
The Top 10 Worst Cities For Seasonal Allergies In 2026
1. Boise, Idaho
2. San Diego, California
3. Tulsa, Oklahoma
4. Provo, Utah
5. Rochester, New York
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6. Wichita, Kansas
7. Raleigh, North Carolina
8. Ogden, Utah
9. Spokane, Washington
10. Greenville, South Carolina
Boise, Idaho, tops the list for the first time and researchers believeatmospheric riverscontributed to a spike in pollen levels there and in many parts of the West. The heavy rain and wet winter can make plants grow faster and bloom earlier — leading to more pollen in the air.
Warmer temperatures due to climate change and drought conditions in other parts of the West, like Utah, also have an impact on how much pollen plants produce, how far it travels and how long it sticks around.
(MORE:Must Of The West Had Warmest Winter On Record)
Be sure to check out ourcomplete guideon allergy season and learn how you can prepare for high pollen days where you live.