San Diego pollen forecast - today, tomorrow and the week ahead

On 30 August 2026, overall pollen levels in San Diego are moderate. Ambrosia is the main contributor to airborne pollen, while grass and artemisia remain at lower levels

On 31 August 2026, pollen conditions in San Diego will be similar to today, with ambrosia at moderate levels, artemisia at low levels, grass at moderate levels

According to the five-day outlook, ambrosia, artemisia, and grass pollen levels will increase later in the week.

On 30 August 2026, Ambrosia is the dominant pollen source in San Diego. grass and artemisia are also present but at lower levels. cypress are not currently active.

San Diego's pollen season opens early, with acacia, olive, and eucalyptus contributing from January in the mild coastal climate. Grass pollen peaks through March and April, earlier than most US cities. The coastal position means onshore Pacific winds frequently disperse urban pollen, while the dry summer largely suppresses mid-season exposure. Chaparral and coastal sage scrub in surrounding canyons contribute seasonal scrub pollen when winds blow from the east.

The San Diego pollen forecast is updated four times daily. See the timestamp below for the most recent update.

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.

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 Diego, 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.