Administration, San Bruno Pollen Forecast - Today, Tomorrow and the Week Ahead
Pollen Today
Today (11 October) pollen in Administration, San Bruno is moderate; ragweed is moderate; mold (alternaria) and mold (cladosporium) are low.
Pollen Tomorrow
Tomorrow (12 October 2026) levels are similar to today.
7-Day Trend
Over the next week grass, mugwort, ragweed, mold (alternaria), and mold (cladosporium) will increase.
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Pollen Risk
Today - 11 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) | Moderate | 30/100 |
| Mold (Alternaria) | Low | 4/100 |
| Mold (Cladosporium) | Low | 11/100 |
Tomorrow - 12 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) | None | 0/100 | |
| Willow (Salicaceae) | None | 0/100 | — |
| Mugwort (Artemisia) | None | 0/100 | |
| Ragweed (Ambrosia) | Moderate | 36/100 | |
| Mold (Alternaria) | Low | 5/100 | |
| Mold (Cladosporium) | Low | 11/100 |
Local Environmental Conditions
This site in San Bruno is surrounded mainly by built-up land, which covers around 65% of the nearby area, with some open water. Grasses also feature strongly, alongside plantain and pigweed among the weeds. Locally, street trees, gardens and lawns supply most pollen in the built-up parts. Roadside verges and patches of open ground provide further room for grasses and weeds.
Then come the grasses, strongest in early fall and fading by mid-fall. Plantain and pigweed bring a final peak from early summer into mid-fall. Winter is the wettest time of year, and heavy showers can bring short breaks in pollen. Dry, sunny and breezy weather raises levels within each period, and steady rain brings them down.
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Pollen forecast neighborhoods 2 neighborhoods
Frequently Asked Questions About Pollen in California
Is pollen high in San Bruno right now?
On 11 October 2026, overall pollen levels in San Bruno are moderate. Ambrosia is the main contributor to airborne pollen
Will pollen levels change in San Bruno tomorrow?
On 12 October 2026, pollen conditions in San Bruno will be similar to today, with ambrosia at moderate levels
Is pollen expected to decrease in San Bruno this week?
According to the five-day outlook, ambrosia, artemisia, and grass pollen levels will increase later in the week.
Which pollen types are currently active in San Bruno?
On 11 October 2026, Ambrosia is the dominant pollen source in San Bruno. artemisia and grass are not currently active.
When is pollen season in San Bruno?
How often is the San Bruno pollen forecast updated?
The San Bruno pollen forecast is updated four times daily. See the timestamp below for the most recent update.
Does pollen in San Bruno 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 San Bruno 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 San Bruno, 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).
