Horsham pollen forecast - today, tomorrow and the week ahead

On 16 July 2026, overall pollen levels in Horsham are moderate. Grass is the main contributor to airborne pollen

On 17 July 2026, pollen conditions in Horsham will be different from today, with grass continuing to decline

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

On 16 July 2026, Grass is the dominant pollen source in Horsham. birch, hazel, cypress, willow, alder, and artemisia are not currently active.

Horsham's pollen year has two main tree culprits: sycamore first, oak close behind. Sycamore pollen typically runs from April to June, and oak keeps things going from April right through to May. Grass pollen then stretches from May into September, with the worst of it typically landing in June and July. Handy to bear in mind before booking that garden party.

The Horsham 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 Horsham, 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.