Fog in Yankton, SD

daily fog outlook & 2016–2026 climatology
Fog unlikely through Monday (peak 8%). August typically brings about 6 hours of dense fog here.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at Chan Gurney Municipal Airport (KYKN). Forecast percentages for this station have passed live verification.

Measuring station

stationairportfog hours/yrforecast
KYKNChan Gurney Municipal Airport57 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 Yankton fogs in

Fog here concentrates in December and January — about 57 hours in a typical year at KYKN, usually lasting ~1 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the KYKN station page.

Fog season

January: ~10 hJanFebruary: ~8 hFebMarch: ~5 hMarApril: ~2 hAprMay: ~2 hMayJune: ~1 hJunJuly: ~4 hJulAugust: ~6 hAugSeptember: ~3 hSepOctober: ~1 hOctNovember: ~4 hNovDecember: ~11 hDec
Fog season is January, February, March, July, August, September, November, December, peaking in December; fog is mostly a 3 AM–8 AM phenomenon; typically thinning out by 10 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.