Low Pollen in O'Fallon, MO

Low today, mostly grass pollen.

Last updated July 1, 2026

Today's index2out of 5Low
GrassLowoff-season

What to do today

  • It's a good day for outdoor activities since pollen levels are low.
  • Do you know which plants cause your pollen allergy? Check out the pollen data to be prepared.

Forecast

Thu
1
Fri
1
Sat
1
Sun
1

About pollen in O'Fallon

Grass pollen is the main player in O'Fallon today, sitting at a Low level of 2 on the index, which puts overall pollen at the same modest reading. The forecast shows grass holding at 2 for another day or so before easing to 1 through the rest of the five-day window, so conditions look to settle gradually. This fits the season, as grasses tend to dominate through late spring and early summer while the spring tree surge from local species like oak, maple, and birch has long since faded. Weed pollen, including the ragweed that typically arrives later in summer and into fall, isn't a factor yet. With no tree or weed data reported, grass is the only measured driver right now, and even that stays in the lower range.

Common questions

What is the pollen count in O'Fallon, MO today?
O'Fallon, MO is at a low 2 out of 5 on the Universal Pollen Index today, driven mainly by grass pollen. Over the next five days it ranges from 1 to 2 of 5.
Is grass pollen high in O'Fallon, MO right now?
Grass pollen is low today at 2 of 5, and it's past its peak season. Most people won't have symptoms.