Alder Creek Falls, Yosemite Valley Pollen Forecast - Today, Tomorrow and the Week Ahead
Pollen Today
Today (7 October) pollen in Alder Creek Falls, Yosemite Valley is moderate; mold (cladosporium) is moderate; ragweed and mold (alternaria) are low.
Pollen Tomorrow
Tomorrow (8 October 2026) ragweed remains low, mold (alternaria) remains low, mold (cladosporium) remains moderate, grass at low levels, mugwort at low levels.
7-Day Trend
Over the next week grass and mugwort will increase; ragweed, mold (alternaria), and mold (cladosporium) will decrease.
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Pollen Risk
Today - 7 October
| 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) | Low | 5/100 |
| Alternaria | Low | 18/100 |
| Cladosporium | Moderate | 29/100 |
Tomorrow - 8 October
| 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 | 4/100 | |
| Ragweed (Ambrosia) | Low | 9/100 | |
| Alternaria | Low | 17/100 | |
| Cladosporium | Moderate | 30/100 |
Local Environmental Conditions
The area around this location in Yosemite Valley is heavily wooded. With running water close by, riverside vegetation contributes to the local mix. Among allergenic trees nearby, oak is the main source. Grasses and weeds such as plantain round out the local mix. Undergrowth, clearings and woodland edges add smaller amounts of grass and herb pollen.
Tree pollen peaks in mid-spring, when the weather warms to around 15°C and oak is in full flower. Grasses take over in late spring, with temperatures around 20°C, and their pollen lingers into early fall. Plantain flowers through much of the warmer half of the year. Winter is the wettest time of year, and heavy showers can bring short breaks in pollen. By early winter, pollen levels are low again.
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Frequently Asked Questions About Pollen in California
Is pollen high in Yosemite Valley right now?
On 7 October 2026, overall pollen levels in Yosemite Valley are low. Ambrosia is the main contributor to airborne pollen
Will pollen levels change in Yosemite Valley tomorrow?
On 8 October 2026, pollen conditions in Yosemite Valley will be different from today, with grass at low levels, ambrosia at low levels, artemisia at low levels
Is pollen expected to decrease in Yosemite Valley this week?
According to the five-day outlook, ambrosia pollen levels are expected to gradually decrease, while grass and artemisia pollen will increase, suggesting mixed conditions later in the week.
Which pollen types are currently active in Yosemite Valley?
On 7 October 2026, Ambrosia is the dominant pollen source in Yosemite Valley. grass and artemisia are not currently active.
When is pollen season in Yosemite Valley?
How often is the Yosemite Valley pollen forecast updated?
The Yosemite Valley pollen forecast is updated four times daily. See the timestamp below for the most recent update.
Does pollen in Yosemite Valley 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 Yosemite Valley 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 Yosemite Valley, 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 pollen scores represent risk levels, not direct pollen measurements. Higher scores indicate higher risk.
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).