Idaho Falls pollen forecast - today, tomorrow and the week ahead
Pollen Today
Today (20 September) pollen in Idaho Falls is high; ragweed is high; grass and mugwort are low.
Pollen Tomorrow
Tomorrow (21 September 2026) levels are similar to today.
7-Day Trend
Over the next week grass, mugwort, and ragweed will decrease.
Explore Forecasts
Air Quality
Pollen for Neighborhoods
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 | 9/100 |
| Willow (Salicaceae) | None | 0/100 |
| Mugwort (Artemisia) | Low | 11/100 |
| Ragweed (Ambrosia) | High | 58/100 |
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 | 18/100 | |
| Willow (Salicaceae) | None | 0/100 | — |
| Mugwort (Artemisia) | Low | 21/100 | |
| Ragweed (Ambrosia) | High | 66/100 |
Local Environmental Conditions
Idaho Falls' parks, including Tautphaus Park and the Snake River corridor, feature cottonwood, birch, and ash as the main tree pollen sources, with exposure varying between these green areas and the more built-up city centre. Surrounding eastern Idaho farmland and the Snake River Plain contribute substantial grass and sagebrush pollen, while the valley setting channels airflows and concentrates pollen across the city.
Idaho Falls' pollen season opens with cottonwood and birch from late February, followed by ash through March and April. Grass pollen peaks through May and June. The enclosed Snake River valley setting can concentrate pollen under calm spring conditions, while surrounding eastern Idaho farmland and the high desert landscape contribute substantial grass and sagebrush pollen. The semi-arid climate means fewer rainfall interruptions than in wetter US cities.
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
Pollen forecast neighborhoods 1 neighborhood
Frequently Asked Questions About Pollen in Idaho
Is pollen high in Idaho Falls right now?
On 20 September 2026, overall pollen levels in Idaho Falls are high. Ambrosia is the main contributor to airborne pollen, while artemisia and grass remain at lower levels
Will pollen levels change in Idaho Falls tomorrow?
On 21 September 2026, pollen conditions in Idaho Falls will be similar to today, with ambrosia at high levels, artemisia at low levels, grass at low levels
Is pollen expected to decrease in Idaho Falls 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 Idaho Falls?
On 20 September 2026, Ambrosia is the dominant pollen source in Idaho Falls. artemisia and grass are also present but at lower levels.
When is pollen season in Idaho Falls?
How often is the Idaho Falls pollen forecast updated?
The Idaho Falls pollen forecast is updated four times daily. See the timestamp below for the most recent update.
Does pollen in Idaho Falls 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 Idaho Falls 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 Idaho Falls, 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).
