Keene, New Hampshire pollen forecast - today, tomorrow and the week ahead
Pollen Today
Today (20 September) pollen in Keene, New Hampshire is low; grass and ragweed are low.
Pollen Tomorrow
Tomorrow (21 September 2026) grass increasing, ragweed increasing, mugwort at low levels.
7-Day Trend
Over the next week grass, mugwort, and ragweed will decrease.
Explore Forecasts
Air Quality
Pollen in Other Cities
Air Quality in Other Cities
Get More in Our App
Local pollen and air quality forecasts, interactive pollen maps and route profiles
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) | Low | 7/100 |
| Willow (Salicaceae) | None | 0/100 |
| Mugwort (Artemisia) | None | 0/100 |
| Ragweed (Ambrosia) | Low | 24/100 |
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 | 40/100 | |
| Willow (Salicaceae) | None | 0/100 | — |
| Mugwort (Artemisia) | Low | 19/100 | |
| Ragweed (Ambrosia) | High | 58/100 |
Local Environmental Conditions
Set on a valley town ringed by the Monadnock highlands, Keene's landscape is defined by sugar maple and beech forest alongside hemlock groves and hayfields, the main contributors to seasonal pollen exposure. Counts here rise and fall with the same broad rhythm as other places sharing this setting. Nearby towns with similar terrain tend to see a broadly similar pattern.
The pollen calendar in Keene opens with maple and elm starting March then birch and oak follows, running through April and May. Grass follows, peaking through June and July, while a modest weed pollen tail continues into September. The New England climate compresses tree, grass, and weed pollen into a shorter but intense season, a defining feature of the local season.
Get pollen & AQ on Strava
Follow your environmental exposure and performance with the free Airmine-Strava integration. See your pollen and air quality exposure for every Strava activity.
Resource Hub
Frequently Asked Questions About Pollen in New Hampshire
Is pollen high in Keene, New Hampshire right now?
On 20 September 2026, overall pollen levels in Keene, New Hampshire are low. Ambrosia is the main contributor to airborne pollen, while grass remain at lower levels
Will pollen levels change in Keene, New Hampshire tomorrow?
On 21 September 2026, pollen conditions in Keene, New Hampshire will be different from today, with artemisia at low levels and ambrosia, grass increasing
Is pollen expected to decrease in Keene, New Hampshire 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 Keene, New Hampshire?
On 20 September 2026, Ambrosia is the dominant pollen source in Keene, New Hampshire. grass are also present but at lower levels. artemisia are not currently active.
When is pollen season in Keene, New Hampshire?
How often is the Keene, New Hampshire pollen forecast updated?
The Keene, New Hampshire pollen forecast is updated four times daily. See the timestamp below for the most recent update.
Does pollen in Keene, New Hampshire 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 Keene, New Hampshire 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 Keene, New Hampshire, 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).
