Willimantic pollen forecast - today, tomorrow and the week ahead
Pollen Today
Today (20 September) pollen in Willimantic is moderate; ragweed is moderate; grass is low.
Pollen Tomorrow
Tomorrow (21 September 2026) ragweed remains moderate, grass increasing, mugwort at low levels.
7-Day Trend
Over the next week grass, mugwort, and ragweed will decrease.
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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) | Low | 22/100 |
| Willow (Salicaceae) | None | 0/100 |
| Mugwort (Artemisia) | None | 0/100 |
| Ragweed (Ambrosia) | Moderate | 36/100 |
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) | Moderate | 36/100 | |
| Willow (Salicaceae) | None | 0/100 | — |
| Mugwort (Artemisia) | Low | 13/100 | |
| Ragweed (Ambrosia) | Moderate | 50/100 |
Local Environmental Conditions
Set on a mill town along the Willimantic and Natchaug Rivers, Willimantic's landscape is defined by oak and maple woodlots alongside riverside sycamore and suburban lawns, the main contributors to seasonal pollen exposure. Wind patterns across the area help determine how far pollen travels from these source plants. As with most of the region, counts tend to build gradually rather than spike overnight.
In Willimantic, pollen season begins with maple and elm starting in March with birch and oak taking the lead through April and May. Grass pollen builds through June and July, and a modest weed pollen tail continues into September. A relatively short growing season compresses tree, grass, and weed pollen into a more intense stretch, a defining feature of the local season.
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Frequently Asked Questions About Pollen in Connecticut
Is pollen high in Willimantic right now?
On 20 September 2026, overall pollen levels in Willimantic are moderate. Ambrosia is the main contributor to airborne pollen, while grass remain at lower levels
Will pollen levels change in Willimantic tomorrow?
On 21 September 2026, pollen conditions in Willimantic will be different from today, with ambrosia at moderate levels, artemisia at low levels and grass increasing
Is pollen expected to decrease in Willimantic this week?
According to the five-day outlook, ambrosia, artemisia, and grass pollen levels are expected to gradually decrease, suggesting improving conditions later in the week.
Which pollen types are currently active in Willimantic?
On 20 September 2026, Ambrosia is the dominant pollen source in Willimantic. grass are also present but at lower levels. artemisia are not currently active.
When is pollen season in Willimantic?
How often is the Willimantic pollen forecast updated?
The Willimantic pollen forecast is updated four times daily. See the timestamp below for the most recent update.
Does pollen in Willimantic 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 Willimantic 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 Willimantic, 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).
