Ohio pollen and allergy seasons
Ohio has a spring tree season and one of the heavier ragweed seasons in the country in late summer.
Twelve month pollen calendar
What is active in September
Cities in Ohio
No tracked cities yet for Ohio.
Today and worst today come from live readings where available. Typical shows the usual level for this month from the seasonal profile.
Pollen is only half of what's in the air. See today's air quality in Ohio for ozone, dust, and smoke readings by city.
The Ohio allergy season
Allergy levels in Ohio peak in September, when ragweed pollen runs highest. The season moves through tree pollen around April, grass in June, weed pollen such as ragweed in September. Levels start to climb around March. The lowest pollen levels of the year arrive in January.
Common questions
When does allergy season start in Ohio?
Pollen levels in Ohio usually begin climbing in March and reach their highest point in September.
What is the worst month for allergies in Ohio?
September is typically the worst month in Ohio, driven by ragweed pollen.
When does ragweed season end in Ohio?
Ragweed pollen in Ohio usually fades by the end of October, after the first hard frost in colder areas.
When is the best time for allergies in Ohio?
January usually brings the lowest pollen levels of the year in Ohio.