Achoo! Allergy Sufferers Beware: Boise Ranks #1 in U.S.

Boise’s winter may not have been exceptionally snowy, but it was certainly wet.When you pair the extra moisture with unseasonably warm temperatures, it’s the perfect storm for an earlier than normal allergy season. In fact, experts say the combination of those things makes for a more intense allergy season too. 

It’s so early in the year that we didn’t even think that the headache and itchy eyes we’ve been dealing with the last few days may have been our seasonal allergies acting up. However, we made the connection when the morning news shared a new ranking from the Asthma and Allergy Foundation of America. 

READ MORE: Idaho Should Be on High Alert For These 9 Extremely Toxic Plants

The foundation took a deep dive into tree, grass and weed pollen counts in America’s 100 largest cities, how many calendar days recorded high pollen counts, the number of over-the-counter allergy medicines sold and the number of allergists in each city to determine America's “Allergy Capitals.”

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When they published the 2026 ranking, Boise was named #1 on the list. Yes, you read that correctly. Out of all 100 cities they evaluated, Boise, Idaho, is America’s worst city for allergy sufferers.

The study explains that this year’s rankings are based on 2025’s pollen data. The experts who prepared the report say the following factors contributed to Boise jumping from #95 on the previous list to #1 on this year’s list: 

• Tree pollen peaking early
• Grass pollen season started earlier than normal
• Grass pollen season lasted longer than normal
• Significantly more days recorded high grass pollen numbers
• Weed pollen season lasted longer than normal
• Weed pollen peaked higher
• Significantly more days recorded high weed pollen numbers
• Fewer allergy specialists available

So which plants are the ones most likely to cause your allergy symptoms in the spring? Archived pollen counts show that these plants are the ones that usually have the highest pollen counts throughout the spring season.