Markham pollen forecast — Thornlea neighborhood

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

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

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

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

Hazel and willow by the water are typically first out of the gate, building through the tail end of winter into March. The nearby oak and birch stands take the lead as spring progresses, usually hitting its highest point sometime between mid-April and mid-May. By late spring, grass pollen is climbing steadily toward a June high point, with ragweed climbing to its own high point from mid-August through October.

The Markham 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 Markham, 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.