Chehalis pollen forecast - today, tomorrow and the week ahead

Today (30 August) pollen in Chehalis is high; grass and ragweed are high; mugwort is moderate. Tomorrow (31 August 2026) levels are similar. 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.

Get the full experience in the Airmine app.

Developed with support from the European Space Agency (ESA)’s Business Applications and Space Solutions (BASS) team

Follow your pollen exposure and performance with the free Airmine–Strava integration. See your pollen and air quality exposure for every Strava activity.

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 - 30 August

  • Alder (Alnus):

    None

    0/100

  • Birch (Betula):

    None

    0/100

  • Hazel (Corylus):

    None

    0/100

  • Cypress (Cupressaceae):

    None

    0/100

  • Grass (Poaceae):

    High

    58/100

  • Willow (Salicaceae):

    None

    0/100

  • Mugwort (Artemisia):

    Moderate

    43/100

  • Ragweed (Ambrosia):

    High

    70/100

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 - 31 August

  • Alder (Alnus):

    None

    0/100

  • Birch (Betula):

    None

    0/100

  • Hazel (Corylus):

    None

    0/100

  • Cypress (Cupressaceae):

    None

    0/100

  • Grass (Poaceae):

    High

    65/100

  • Willow (Salicaceae):

    None

    0/100

  • Mugwort (Artemisia):

    Moderate

    50/100

  • Ragweed (Ambrosia):

    High

    70/100

Air quality in Chehalis

View air quality

Frequently Asked Questions

Is pollen high in Chehalis right now?

On 30 August 2026, overall pollen levels in Chehalis are high. Ambrosia is the main contributor to airborne pollen, while grass and artemisia remain at lower levels

Will pollen levels change in Chehalis tomorrow?

On 31 August 2026, pollen conditions in Chehalis will be similar to today, with ambrosia at high levels, artemisia at moderate levels, grass at high levels

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 30 August 2026, Ambrosia is the dominant pollen source in Chehalis. grass and artemisia are also present but at lower levels. cypress are not currently active.

When is pollen season in Chehalis?
Chehalis's pollen season opens with alder and birch from February with maple taking the lead through March and April. A grass pollen peak follows through May and June; plantain and nettle stretch the season into September. Frequent spring rain across the Pacific Northwest periodically clears pollen from the air, moderating peak counts, a defining feature of the local season.
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: 30 August 2026 at 08:36 CEST (Data is updated four times daily.)

This page provides the latest public pollen forecast for Chehalis.

Get the full experience in the Airmine app.

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.

Some text on this page may be generated or summarised using artificial intelligence (AI). Wherever possible, AI-generated content is enriched with Airmine's proprietary data to improve its accuracy and relevance. However, AI-generated content may still contain errors, omissions, or inaccuracies.