Portland pollen forecast — Forest Park neighborhood

Currently, there is no significant pollen in Portland.

On 26 June 2026, pollen conditions in Portland will be similar to today with no significant pollen expected.

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

On 25 June 2026, there are no significant pollen types in Portland.

Portland Forest Park occupies the largest urban forest in the US running along the Tualatin Mountain ridge above Portland, where Douglas fir, alder, and bigleaf maple are the main pollen sources across this extensive Pacific Northwest forest. The enclosed forest concentrates pollen under calm conditions, while alder peaks strongly through March and April, grass from forest clearings peaks through June and July, and mugwort extends into September throughout this remarkable Portland urban forest wilderness.

The Portland 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 Portland, 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.