Fog in Eureka, CA

daily fog outlook & 2016–2026 climatology
Fog possible — NWS guidance shows a fog signal in the next 48 hours. August typically brings about 7 hours of dense fog here.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at Murray Field (KEKA). This station is in forecast verification — percentages publish when it clears the accuracy bar.

Measuring station

stationairportfog hours/yrforecast
KEKAMurray Field173 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 Eureka fogs in

Fog here concentrates in October and March — about 173 hours in a typical year at KEKA, usually lasting ~1 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the KEKA station page.

Fog season

January: ~2 hJanFebruary: ~1 hFebMarch: ~31 hMarApril: ~0 hAprMay: ~2 hMayJune: ~2 hJunJuly: ~12 hJulAugust: ~7 hAugSeptember: ~16 hSepOctober: ~46 hOctNovember: ~0 hNovDecember: ~3 hDec
Fog season is March, July, September, October, peaking in October; fog is mostly a 3 AM–3 AM phenomenon; typically thinning out by 4 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.