Missouri pollen and allergy seasons
Missouri has a spring tree season and a heavy ragweed season in late summer and early fall.
Twelve month pollen calendar
What is active in September
Cities in Missouri
No tracked cities yet for Missouri.
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 Missouri for ozone, dust, and smoke readings by city.
The Missouri allergy season
Allergy levels in Missouri 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 February. The lowest pollen levels of the year arrive in January.
Common questions
When does allergy season start in Missouri?
Pollen levels in Missouri usually begin climbing in February and reach their highest point in September.
What is the worst month for allergies in Missouri?
September is typically the worst month in Missouri, driven by ragweed pollen.
When does ragweed season end in Missouri?
Ragweed pollen in Missouri usually fades by the end of October, after the first hard frost in colder areas.
When is the best time for allergies in Missouri?
January usually brings the lowest pollen levels of the year in Missouri.