St Louis, MO Pollen Count Today

Live pollen forecast and air quality for St Louis, Missouri

šŸ“ St Louis, MOToday Ā· Sep 20
6/10
Breathabilityā„¢ Score
Good day overall with a few allergy-aware adjustments.
šŸŒ³Tree Pollen
None
šŸŒ±Grass Pollen
None
šŸŒæWeed Pollen
Moderate
mypollenpal.comAdd to your site ā†’

Today's Pollen Levels in St Louis

Weed pollen is slightly elevated at Moderate levels in St Louis. Overall conditions are manageable for most people. With a Breathabilityā„¢ Score of 6, conditions are mixed and may vary through the day.

How Today's Pollen May Affect You

Mild allergy sufferers
You may notice mild irritation at peak times. Weed pollen is elevated; consider shorter midday exposure and keep water handy.
Moderate allergy sufferers
Plan around peak pollen windows. Try errands early or later, and consider a mask in high-traffic outdoor areas.
Severe allergy sufferers
Use high-protection habits today: shorter trips, cleaner indoor air, and reduced exposure during peak pollen hours.

5-Day Pollen Forecast

Pollen in St Louis peaks Tuesday at High, driven by weed pollen.

Today
Sep 20
Overall: Moderate
Tree: None
Grass: None
Weed: Moderate
Wind: 12 mph
Rain: 57% (may wash pollen out)
Humidity: 46%
Mon
Sep 21
Overall: Moderate
Tree: None
Grass: None
Weed: Moderate
Wind: 10 mph
Rain: 78% (may wash pollen out)
Humidity: 82%
Tue
Sep 22
Overall: High
Tree: None
Grass: None
Weed: High
Wind: 9 mph
Rain: 16%
Humidity: 67%
Wed
Sep 23
Overall: High
Tree: None
Grass: None
Weed: High
Wind: 11 mph
Rain: 6%
Humidity: 60%
Thu
Sep 24
Overall: High
Tree: None
Grass: None
Weed: High
Wind: 9 mph
Rain: 6%
Humidity: 68%

Rain is likely Monday (78% chance). The hour or two right after it stops is usually the cleanest air of the day. Plan around Tuesday though. Pollen often climbs the day after rain, when plants use the moisture to release a fresh burst.

Tree Pollen in St Louis Today

Tree pollen in St Louis is None today. Tree pollen season typically runs from early spring through late May, peaking when deciduous trees release their pollen. On low days like today, outdoor activities are generally comfortable for most allergy sufferers.

Species Breakdown

Alder0 grains/mĀ³
Birch0 grains/mĀ³
Hazel0 grains/mĀ³
Oak0 grains/mĀ³

Grass Pollen in St Louis Today

Grass pollen in St Louis is None today. Grass pollen season typically peaks from late spring through summer (May through August in most regions). On low-count days, grass allergy sufferers can generally spend time outdoors without significant symptoms.

Species Breakdown

Grass0 grains/mĀ³

Weed Pollen in St Louis Today

Weed pollen in St Louis is Moderate today, reaching 49.86 grains/mĀ³. Ragweed and Mugwort are the primary driver. Ragweed is the most common allergen in this category, and elevated levels can trigger persistent symptoms even in people who are only mildly sensitive.

Common Symptoms

  • Persistent sneezing
  • Runny nose
  • Itchy eyes and throat
  • Nasal congestion
  • Fatigue from prolonged exposure

Species Breakdown

Ragweed49.86 grains/mĀ³
Mugwort10.66 grains/mĀ³

Air Quality in St Louis Today

šŸŒ¬ļø
Air Quality
Good
Good

Air Pollutant Breakdown

PM2.5Good
10 Āµg/mĀ³
Tiny particles smaller than 2.5 micrometers that can reach deep into your lungs and bloodstream. High levels can affect breathing and heart health.
PM10Good
10 Āµg/mĀ³
Larger particles up to 10 micrometers, like dust or pollen. They can irritate your airways and worsen allergies or asthma.
Ozone (O3)Good
34 Āµg/mĀ³
Elevated levels irritate airways and can worsen asthma symptoms.
Nitrogen Dioxide (NO2)Good
20.2 Āµg/mĀ³
A respiratory irritant from vehicle exhaust that can trigger inflammation in sensitive airways.
Sulfur Dioxide (SO2)Good
2.2 Āµg/mĀ³
Even brief exposure can tighten airways, especially for people with asthma.
Carbon Monoxide (CO)Good
277 Āµg/mĀ³
High levels reduce oxygen delivery in the body, compounding breathing difficulty on high-pollen days.
See the full St Louis air quality report ā†’

Weather in St Louis Today

šŸŒ¤ļø
Weather
84Ā°F
Overcast
Humidity
36%
Wind
9 mph SW
Feels Like
80Ā°F
Pressure
1011 mb

Frequently Asked Questions

When pollen keeps winning, see an allergist

Pollen shifts week to week in St Louis. If cetirizine (Zyrtec) or a steroid nasal spray stopped holding your symptoms down, or they drag on for months at a time, a board-certified allergist can test exactly what you react to and treat the cause instead of the symptom.

See 5 board-certified allergists in Missouri ā†’

Get free daily pollen alerts

Morning alerts for St Louis when pollen is high. One email a day, only when it matters.

Sign up free ā†’

Allergy Guides and Resources

Seasonal pollen guides, daily city rankings, and practical tips for managing your allergies.

Browse all guides ā†’

Related Cities in Missouri

Looking for more places? Browse popular cities or return to the Missouri page.