Ontario Pollen Forecast
Live pollen counts, AQHI air quality, and weather across Ontario, Canada — for parents, outdoor planners, and anyone managing seasonal allergies. Updated hourly.
About the AQHI (Air Quality Health Index)
Canada uses the Air Quality Health Index (AQHI), a 1-10+ scale developed by Environment Canada. It's the number you see on weather.gc.ca and on local news. Lower is better.
- 1-3 — Low Risk: Ideal air quality for outdoor activities
- 4-6 — Moderate Risk: Consider reducing strenuous outdoor exercise if you have asthma
- 7-10 — High Risk: Limit outdoor time, especially for children and those with respiratory conditions
Cities in Ontario
Largest Canadian metro
Toronto, Ontario
Ontario's Allergy Season
Ontario's pollen season typically runs from April through October. Tree pollen (maple, birch, oak, alder) leads in April-May, grass pollen peaks in June-July, and ragweed dominates August through first frost — often into mid-October across southern Ontario. Long winters keep early-year counts low, but spring melt triggers a fast ramp-up.
Looking for Canadian cities outside Ontario? Browse all provinces →
Looking for Ontario, California (the city in San Bernardino County, USA)? See the Ontario, CA city page →