Fog in Fort Lewis/Tacoma, WA

daily fog outlook & 2016–2026 climatology
No fog signal in NWS guidance for the next 48 hours. August typically brings about 1 hour of dense fog here.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at Gray Army Air Field (KGRF). This station is in forecast verification — percentages publish when it clears the accuracy bar.

Measuring station

stationairportfog hours/yrforecast
KGRFGray Army Air Field95 h/yrverifying

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 Lewis/Tacoma fogs in

Fog here concentrates in December and January — about 95 hours in a typical year at KGRF, usually lasting ~1 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the KGRF station page.

Fog season

January: ~22 hJanFebruary: ~11 hFebMarch: ~3 hMarApril: ~1 hAprMay: ~2 hMayJune: ~0 hJunJuly: ~0 hJulAugust: ~1 hAugSeptember: ~3 hSepOctober: ~10 hOctNovember: ~19 hNovDecember: ~25 hDec
Fog season runs October through February, peaking in December; fog is mostly a 3 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.