Fog in Peoria, IL

daily fog outlook & 2016–2026 climatology
No fog signal in NWS guidance for the next 48 hours. 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 General Wayne A. Downing Peoria International Airport (KPIA). This station is in forecast verification — percentages publish when it clears the accuracy bar.

Measuring station

stationairportfog hours/yrforecast
KPIAGeneral Wayne A. Downing Peoria International Airport41 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 Peoria fogs in

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

Fog season

January: ~12 hJanFebruary: ~7 hFebMarch: ~3 hMarApril: ~1 hAprMay: ~3 hMayJune: ~1 hJunJuly: ~1 hJulAugust: ~1 hAugSeptember: ~2 hSepOctober: ~1 hOctNovember: ~4 hNovDecember: ~5 hDec
Fog season is January, February, March, May, November, December, peaking in January; fog is mostly a 5 AM–9 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.