KACV — California Redwood Coast-Humboldt County Airport

fog forecast & climatology · Arcata/Eureka city page · full 10-year analysis →
Fog possible — NWS guidance shows a fog signal in the next 48 hours. September typically brings about 41 hours of dense fog here.forecast cycle 2026-09-04T13:00:00Z · page rebuilt daily · live layers below update hourly

Fog hours per year
253 h below CAT I minima (2016–2026 average)
Fog season
October and September
Typical fog event
~1 h once it forms (middle half 1–3 h, n=1258)
Data through
2026-08-15 · machine-readable data.json

When this airport fogs in

In a typical year California Redwood Coast-Humboldt County Airport spends 253 hours below CAT I approach minima (visibility under ~½ mile or ceiling under 200 ft), concentrated in October and September. The strip above shows the hour-by-hour pattern for the current month from ten years of weather observations.

Fog season

January: ~14 hJanFebruary: ~10 hFebMarch: ~10 hMarApril: ~7 hAprMay: ~8 hMayJune: ~16 hJunJuly: ~27 hJulAugust: ~40 hAugSeptember: ~41 hSepOctober: ~53 hOctNovember: ~20 hNovDecember: ~11 hDec
Fog season is January, June, July, August, September, October, November, peaking in October; fog is mostly a 11 PM–8 AM phenomenon; typically thinning out by 10 AM; a typical event lasts about 1 hour once it forms local time · 10-yr average

Runway infrastructure

endapproach lightsbest approachlengthRVR
01—LPV4,501 ft—
19——4,501 ft—
14—LPV6,046 ftRVR
32MALSRCAT I6,046 ftRVR

From FAA NASR / curated AIP Canada research. Approach-light class and minima tier drive how low an approach can be flown — details in the chase board.

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.