Fog in Fort Simpson, NT

daily fog outlook & 2016–2026 climatology
Fog unlikely through Sunday (peak 3%). August typically brings about 4 hours of dense fog here.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at Fort Simpson Airport (CYFS). Forecast percentages for this station have passed live verification.

Measuring station

stationairportfog hours/yrforecast
CYFSFort Simpson Airport42 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 Fort Simpson fogs in

Fog here concentrates in October and September — about 42 hours in a typical year at CYFS, usually lasting ~1 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the CYFS station page.

Fog season

January: ~1 hJanFebruary: ~1 hFebMarch: ~1 hMarApril: ~2 hAprMay: ~0 hMayJune: ~0 hJunJuly: ~5 hJulAugust: ~4 hAugSeptember: ~7 hSepOctober: ~15 hOctNovember: ~4 hNovDecember: ~3 hDec
Fog season runs July through November, peaking in October; fog is mostly a 4 AM–10 AM phenomenon; typically thinning out by 1 PM; 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.