Fog in Des Moines, IA

daily fog outlook & 2016–2026 climatology
Fog unlikely through Sunday (peak 5%). August typically brings about 1 hour of dense fog here.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at Des Moines International Airport (KDSM). Forecast percentages for this station have passed live verification.

Measuring station

stationairportfog hours/yrforecast
KDSMDes Moines International Airport41 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 Des Moines fogs in

Fog here concentrates in December and January — about 41 hours in a typical year at KDSM, usually lasting ~2 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the KDSM station page.

Fog season

January: ~11 hJanFebruary: ~4 hFebMarch: ~2 hMarApril: ~1 hAprMay: ~2 hMayJune: ~0 hJunJuly: ~1 hJulAugust: ~1 hAugSeptember: ~3 hSepOctober: ~3 hOctNovember: ~2 hNovDecember: ~11 hDec
Fog season is January, February, September, October, December, peaking in January; fog is mostly a 5 AM–8 AM phenomenon; typically thinning out by 11 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.