Fog in St Joseph, MO

daily fog outlook & 2016–2026 climatology
Some chance of fog — peaks at 22% around 7 am Monday.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at Rosecrans Memorial Airport (KSTJ). Forecast percentages for this station have passed live verification.

Measuring station

stationairportfog hours/yrforecast
KSTJRosecrans Memorial Airport101 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 St Joseph fogs in

Fog here concentrates in December and September — about 101 hours in a typical year at KSTJ, usually lasting ~2 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the KSTJ station page.

Fog season

January: ~10 hJanFebruary: ~5 hFebMarch: ~4 hMarApril: ~3 hAprMay: ~2 hMayJune: ~3 hJunJuly: ~10 hJulAugust: ~10 hAugSeptember: ~14 hSepOctober: ~13 hOctNovember: ~11 hNovDecember: ~17 hDec
Fog season runs July through February, peaking in December; fog is mostly a 2 AM–7 AM phenomenon; typically thinning out by 9 AM; a typical event lasts about 2 hours once it forms local time · 10-yr average

Machine access: data.json · llms.txt · forecast verification. Not for operational use.