Fog in Santa Ana, CA

daily fog outlook & 2016–2026 climatology
No fog signal in NWS guidance for the next 48 hours. dense fog (visibility under a mile) is rare here in August.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at John Wayne Orange County International Airport (KSNA). This station is in forecast verification — percentages publish when it clears the accuracy bar.

Measuring station

stationairportfog hours/yrforecast
KSNAJohn Wayne Orange County International Airport34 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 Santa Ana fogs in

Fog here concentrates in December and February — about 34 hours in a typical year at KSNA, usually lasting ~1 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the KSNA station page.

Fog season

January: ~4 hJanFebruary: ~7 hFebMarch: ~2 hMarApril: ~1 hAprMay: ~0 hMayJune: ~0 hJunJuly: ~0 hJulAugust: ~0 hAugSeptember: ~1 hSepOctober: ~5 hOctNovember: ~6 hNovDecember: ~9 hDec
Fog season runs October through February, peaking in December; fog is mostly a 2 AM–8 AM phenomenon; typically thinning out by 9 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.