Fog in Thief River Falls, MN

daily fog outlook & 2016–2026 climatology
Some chance of fog — peaks at 23% around 7 am Sunday.forecast cycle 2026-08-16T00:00:00Z · page rebuilt daily · live layers below update hourly

Measured at Thief River Falls Regional Airport (KTVF). Forecast percentages for this station have passed live verification.

Measuring station

stationairportfog hours/yrforecast
KTVFThief River Falls Regional Airport89 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 Thief River Falls fogs in

Fog here concentrates in January and March — about 89 hours in a typical year at KTVF, usually lasting ~2 h once it forms. Hour-by-hour patterns, live conditions and the forecast strip live on the KTVF station page.

Fog season

January: ~18 hJanFebruary: ~12 hFebMarch: ~13 hMarApril: ~5 hAprMay: ~2 hMayJune: ~3 hJunJuly: ~2 hJulAugust: ~5 hAugSeptember: ~4 hSepOctober: ~5 hOctNovember: ~5 hNovDecember: ~13 hDec
Fog season is January, February, March, April, August, October, November, December, peaking in January; fog is mostly a 3 AM–9 AM phenomenon; typically thinning out by 1 PM; 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.