Chehalis pollen forecast - today, tomorrow and the week ahead
Today (9 August) pollen in Chehalis is medium; ragweed is medium; grass and mugwort are low. Tomorrow (10 August 2026) levels are similar - grass increasing, mugwort increasing, ragweed increasing. Over the following five days grass, mugwort, and ragweed will increase. Forecasts are calculated by Airmine using satellites to map local vegetation and determine pollen season onset.
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Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team
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Chehalis's setting on flat farmland along the Chehalis River in southwestern Washington supports riverside cottonwood, Douglas fir forest, and farmland grasses as the leading local vegetation, all factoring into the pollen count through the year. Seasonal timing here follows the broader regional pattern typical of this part of the country. As with most of the region, counts tend to build gradually rather than spike overnight.
Today - 9 August
-
Alder (Alnus):
None
0/100
-
Birch (Betula):
None
0/100
-
Hazel (Corylus):
None
0/100
-
Cypress (Cupressaceae):
None
0/100
-
Grass (Poaceae):
Low
2/100
-
Willow (Salicaceae):
None
0/100
-
Mugwort (Artemisia):
Low
11/100
-
Ragweed (Ambrosia):
Medium
30/100
High pollen levels may trigger sneezing, itchy eyes, and congestion. Airmine's neighbourhood estimates use satellites to map local vegetation and a statistical prediction model, updated four times daily.
Tomorrow - 10 August
-
Alder (Alnus):
None
0/100
-
Birch (Betula):
None
0/100
-
Hazel (Corylus):
None
0/100
-
Cypress (Cupressaceae):
None
0/100
-
Grass (Poaceae):
Medium
30/100
-
Willow (Salicaceae):
None
0/100
-
Mugwort (Artemisia):
Medium
39/100
-
Ragweed (Ambrosia):
High
57/100
Air quality in Chehalis
View air qualityFrequently Asked Questions
Is pollen high in Chehalis right now?
On 9 August 2026, overall pollen levels in Chehalis are moderate. Ambrosia is the main contributor to airborne pollen, while artemisia and grass remain at lower levels
Will pollen levels change in Chehalis tomorrow?
On 10 August 2026, pollen conditions in Chehalis will be different from today, with ambrosia, artemisia, grass increasing
Is pollen expected to decrease in Chehalis this week?
According to the five-day outlook, ambrosia, artemisia, and grass pollen levels will increase later in the week.
Which pollen types are currently active in Chehalis?
On 9 August 2026, Ambrosia is the dominant pollen source in Chehalis. artemisia and grass are also present but at lower levels. cypress are not currently active.
When is pollen season in Chehalis?
How often is the Chehalis pollen forecast updated?
The Chehalis pollen forecast is updated four times daily. See the timestamp below for the most recent update.
Does pollen in Chehalis come from nearby or far away?
Studies show that most pollen exposure (often 70–90%) comes from nearby sources, such as local trees and vegetation. A good pollen forecast therefore depends on accurately representing local vegetation. Pollen can travel long distances, but this usually matters only early in the season or during specific wind events.
Are pollen levels in Chehalis based on measurements or forecasts?
Pollen data is often misunderstood. Most "pollen levels" are not real-time measurements, but forecasts.
Direct pollen measurements are typically delayed by 1-2 days because they require manual analysis. To show current conditions in Chehalis, modern forecasts combine recent measurements, weather data, and information about local vegetation.
This allows us to estimate pollen levels for today and the coming days, not just report the past.
Airmine’s atmospheric monitoring platform was developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team, using satellite and Earth observation technologies to improve emissions monitoring.
Want to see pollen forecasts for other cities in United States?
Check pollen in other popular cities:
Data provided by Airmine — Last update: 9 August 2026 at 20:27 CEST (Data is updated four times daily.)
This page provides the latest public pollen forecast for Chehalis.
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Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.
Disclaimer: Forecasts are provided for informational purposes only and should not be relied upon as medical advice. Actual pollen and air quality conditions may vary from the forecast. If you have allergies, asthma, or another medical condition, consult a healthcare professional. Please see our Terms of Service for important information about limitations of liability.