Northglenn pollen forecast - today, tomorrow and the week ahead
Pollen Today
Today (20 September) pollen in Northglenn is moderate; ragweed is moderate.
Pollen Tomorrow
Tomorrow (21 September 2026) ragweed increasing, grass at low levels, mugwort at low levels.
7-Day Trend
Over the next week grass and mugwort will increase; ragweed will decrease.
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Features and forecast availability vary by region.
Pollen Risk
Today - 20 September
| Pollen species | Level | Value |
|---|---|---|
| Alder (Alnus) | None | 0/100 |
| Birch (Betula) | None | 0/100 |
| Hazel (Corylus) | None | 0/100 |
| Cypress (Cupressaceae) | None | 0/100 |
| Grass (Poaceae) | None | 0/100 |
| Willow (Salicaceae) | None | 0/100 |
| Mugwort (Artemisia) | None | 0/100 |
| Ragweed (Ambrosia) | Moderate | 45/100 |
Tomorrow - 21 September
| Pollen species | Level | Value | 7-Day Trend |
|---|---|---|---|
| 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 | 8/100 | |
| Ragweed (Ambrosia) | High | 52/100 |
Local Environmental Conditions
Nearby, close by, cottonwood and willow crowd this rare water source, a green ribbon against the surrounding shortgrass prairie. A park whose lawns and ornamental trees quietly add to grass and ragweed pollen levels, in the wider area. Small shifts in elevation or soil type can move these figures a little either way.
Temperatures here typically swing from about -2°C in January up to 25°C in July; most of the 444 mm annual rainfall falls in the warmer months around July. As temperatures rise out of their January low, pollen activity typically starts picking up from around February.
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Frequently Asked Questions About Pollen in Colorado
Is pollen high in Northglenn right now?
On 20 September 2026, overall pollen levels in Northglenn are moderate. Ambrosia is the main contributor to airborne pollen
Will pollen levels change in Northglenn tomorrow?
On 21 September 2026, pollen conditions in Northglenn will be different from today, with artemisia at low levels, grass at low levels and ambrosia increasing
Is pollen expected to decrease in Northglenn this week?
According to the five-day outlook, ambrosia pollen levels are expected to gradually decrease, while artemisia and grass pollen will increase, suggesting mixed conditions later in the week.
Which pollen types are currently active in Northglenn?
On 20 September 2026, Ambrosia is the dominant pollen source in Northglenn. artemisia and grass are not currently active.
When is pollen season in Northglenn?
How often is the Northglenn pollen forecast updated?
The Northglenn pollen forecast is updated four times daily. See the timestamp below for the most recent update.
Does pollen in Northglenn 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 Northglenn 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 Northglenn, 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.
Understanding the Scale
The 0–100 scores represent risk levels, not direct measurements of pollen or air pollutant concentrations. Higher scores indicate higher risk. Pollen and air quality use different thresholds.
Pollen
| None | 0 | No or negligible risk of exposure. Pollen/mold exposure is expected to be minimal. |
| Low | 0-25 | Low risk of exposure. Small amounts of pollen or mold spores may be present. |
| Moderate | 25-50 | Moderate risk of exposure. Pollen/mold exposure is expected to be noticeable. |
| High | 50-75 | High risk of exposure. Elevated pollen/mold exposure is expected. |
| Very High | 75-100 | Very high risk of exposure. Pollen/mold exposure is expected to be at or near its highest levels. |
Get More in the Airmine Pollen app
Get 15-day pollen forecasts with morning, afternoon and evening detail, plus 5-day air quality forecasts. Explore interactive pollen risk maps, estimated pollen season start, route profiles and a symptoms diary.
Features and forecast availability vary by region. Currently covering Europe, the contiguous US, southern Canada, South Africa, Australia, Indonesia (Java & Bali), Brazil, Paraguay, Uruguay and the Buenos Aires area.
Developed with support from the European Space Agency (ESA) Business Applications and Space Solutions (BASS).
