CYYZ — Toronto Pearson International Airport

fog forecast & climatology · Toronto city page · full 10-year analysis →
No fog signal in NWS guidance for the next 48 hours. dense fog (visibility under a mile) is rare here in September.forecast cycle 2026-09-04T13:00:00Z · page rebuilt daily · live layers below update hourly

Fog hours per year
35 h below CAT I minima (2016–2026 average)
Fog season
January and November
Typical fog event
~1 h once it forms (middle half 1–3 h, n=141)
Data through
2026-08-15 · machine-readable data.json

When this airport fogs in

In a typical year Toronto Pearson International Airport spends 35 hours below CAT I approach minima (visibility under ~½ mile or ceiling under 200 ft), concentrated in January and November. The strip above shows the hour-by-hour pattern for the current month from ten years of weather observations.

Fog season

January: ~8 hJanFebruary: ~5 hFebMarch: ~5 hMarApril: ~2 hAprMay: ~2 hMayJune: ~1 hJunJuly: ~0 hJulAugust: ~0 hAugSeptember: ~0 hSepOctober: ~3 hOctNovember: ~6 hNovDecember: ~4 hDec
Fog season runs October through May, peaking in January; fog is mostly a midnight–11 AM phenomenon; typically thinning out by noon; a typical event lasts about 1 hour once it forms local time · 10-yr average

For flight operations

EFVS crews: the CHASE board ranks airports by live fog status, approach lighting, go-around height and flight time from your base. Forecast probabilities publish here per-airport once the calibrated model beats climatology on live verification — receipts on the scorecard. Methodology.

Sources: NOAA/NWS National Blend of Models guidance · METAR observations 2016–2026 (Iowa Environmental Mesonet) · FAA NASR. Machine access: data.json · llms.txt. Not for operational use.