Fog in Armstrong, ON

daily fog outlook & 2016–2026 climatology
Fog unlikely through Sunday (peak 9%). August typically brings about 10 hours of dense fog here.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at Armstrong Airport (CYYW). Forecast percentages for this station have passed live verification.

Measuring station

stationairportfog hours/yrforecast
CYYWArmstrong Airport66 h/yrlive forecast

Fog is measured where instruments live — airports. Hours/yr = time below CAT I approach minima (visibility under ~½ mile or ceiling under 200 ft), the aviation definition of seriously dense fog.

When Armstrong fogs in

Fog here concentrates in September and August — about 66 hours in a typical year at CYYW, usually lasting ~1 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the CYYW station page.

Fog season

January: ~3 hJanFebruary: ~1 hFebMarch: ~2 hMarApril: ~5 hAprMay: ~6 hMayJune: ~4 hJunJuly: ~7 hJulAugust: ~10 hAugSeptember: ~12 hSepOctober: ~9 hOctNovember: ~5 hNovDecember: ~4 hDec
Fog season runs April through January, peaking in September; fog is mostly a 5 AM–9 AM phenomenon; typically thinning out by 11 AM; a typical event lasts about 1 hour once it forms local time · 10-yr average

Machine access: data.json · llms.txt · forecast verification. Not for operational use.