St. Alliston
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St. Alliston Live Precipitation Radar
Full Screen ViewSt. Alliston Live Doppler RadarMSC Dual-Pol
St. Alliston, ON • Lat: 45.22° N, Lon: 84.99° W • Sweep 10m
St. Alliston 30-Year Weather History & Monthly Averages
Explore month-by-month temperatures, annual snowfall in cm, rainy days, and historical record highs and lows.
St. Alliston Air Quality & Wildfire Smoke Report
Detailed Canadian AQHI breakdown, fine particulate matter (PM2.5), ground-level ozone, and health guidance.
Frequently Asked Questions About Weather in St. Alliston, ON
What is the current temperature and conditions in St. Alliston?
As of today, the temperature in St. Alliston is 20.6°C with clear sky. The apparent temperature (feels like) is 19.6°C with relative humidity at 59%.
How does Wind Chill and Humidex affect St. Alliston?
During warmer conditions, the Canadian Humidex indicates comfort levels. The current Humidex is 21 (Comfortable).
What is the Air Quality Health Index (AQHI) for St. Alliston?
The current AQHI for St. Alliston is 4 (Moderate Risk). It is calculated based on ground-level ozone, fine particulate matter (PM2.5), and nitrogen dioxide levels according to Health Canada standards.
Where does the meteorological data for St. Alliston come from?
Forecasts are generated using high-resolution Canadian Deterministic Prediction System (HRDPS 2.5km) and Global Environmental Multiscale (GEM) models alongside official Environment and Climate Change Canada Doppler radar feeds.