Greeley pollen forecast - today, tomorrow and the week ahead

Today (25 June) pollen in Greeley is low; grass is low. Tomorrow (26 June 2026) levels are similar - grass increasing, willow at low levels. Over the following five days grass and willow will decrease. Forecasts are calculated by Airmine using satellites to map local vegetation and determine pollen season onset.

For long term forecasts and maps, see the Airmine app

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

Greeley's parks, including Glenmere Park and the Cache la Poudre River corridor, feature cottonwood, ash, and oak as the main tree pollen sources, with exposure varying between these green areas and the more built-up city centre. Surrounding Colorado farmland and the open plains contribute substantial grass and crop pollen, while the Front Range setting channels prevailing westerly winds and can concentrate pollen across the city.

Today - 25 June

  • Alder (Alnus):

    None

    0/100

  • Birch (Betula):

    None

    0/100

  • Hazel (Corylus):

    None

    0/100

  • Cypress (Cupressaceae):

    None

    0/100

  • Grass (Poaceae):

    Low

    19/100

  • Willow (Salicaceae):

    None

    0/100

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 - 26 June

  • Alder (Alnus):

    None

    0/100

  • Birch (Betula):

    None

    0/100

  • Hazel (Corylus):

    None

    0/100

  • Cypress (Cupressaceae):

    None

    0/100

  • Grass (Poaceae):

    Medium

    47/100

  • Willow (Salicaceae):

    Low

    21/100

Frequently Asked Questions

Is pollen high in Greeley right now?

On 25 June 2026, overall pollen levels in Greeley are low. Grass is the main contributor to airborne pollen

Will pollen levels change in Greeley tomorrow?

On 26 June 2026, pollen conditions in Greeley will be different from today, with willow at low levels and grass increasing

Is pollen expected to decrease in Greeley this week?

According to the five-day outlook, grass and willow pollen levels are expected to gradually decrease, suggesting improving conditions later in the week.

Which pollen types are currently active in Greeley?

On 25 June 2026, Grass is the dominant pollen source in Greeley. hazel, cypress, and willow are not currently active.

When is pollen season in Greeley?
Greeley's pollen season opens with elm and cottonwood from late February, followed by ash and oak through April and May. Grass pollen peaks through June and July. The Cache la Poudre valley and the Front Range setting channel prevailing westerly winds and can concentrate pollen across the city, while surrounding Colorado farmland contributes substantial grass and crop pollen. The semi-arid climate means fewer rainfall interruptions than in eastern US cities.
How often is the Greeley pollen forecast updated?

The Greeley pollen forecast is updated four times daily. See the timestamp below for the most recent update.

Does pollen in Greeley 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 Greeley 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 Greeley, 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: 25 Jun 2026, 09:02 CET (Data is updated four times daily.)

This page provides the latest public pollen forecast for Greeley.

For long term forecasts and maps, see the Airmine app

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

Unless explicitly made clear, the content on this site has not been paid for by external organisations and is Airmine's sole responsibility.