KSDF — Louisville Muhammad Ali International Airport

fog forecast & climatology · Louisville city page · full 10-year analysis →
No fog signal in NWS guidance for the next 48 hours. September typically brings about 1 hour of dense fog here.forecast cycle 2026-09-04T13:00:00Z · page rebuilt daily · live layers below update hourly

Fog hours per year
11 h below CAT I minima (2016–2026 average)
Fog season
February and March
Typical fog event
~1 h once it forms (middle half 1–3 h, n=48)
Data through
2026-08-15 · machine-readable data.json

When this airport fogs in

In a typical year Louisville Muhammad Ali International Airport spends 11 hours below CAT I approach minima (visibility under ~½ mile or ceiling under 200 ft), concentrated in February and March. The strip above shows the hour-by-hour pattern for the current month from ten years of weather observations.

Fog season

January: ~1 hJanFebruary: ~4 hFebMarch: ~1 hMarApril: ~0 hAprMay: ~1 hMayJune: ~0 hJunJuly: ~0 hJulAugust: ~0 hAugSeptember: ~1 hSepOctober: ~0 hOctNovember: ~1 hNovDecember: ~1 hDec
Fog season is February, peaking in February; fog is mostly a 1 AM–8 AM phenomenon; typically thinning out by 9 AM; a typical event lasts about 1 hour once it forms local time · 10-yr average

Runway infrastructure

endapproach lightsbest approachlengthRVR
117,251 ftRVR
29MALSRLPV7,251 ftRVR
17LMALSRCAT I8,578 ftRVR
35RALSF-2CAT IIIB8,578 ftRVR
17RMALSRCAT I11,887 ftRVR
35LALSF-2CAT IIIB11,887 ftRVR

From FAA NASR / curated AIP Canada research. Approach-light class and minima tier drive how low an approach can be flown — details in the chase board.

For flight operations

EFVS crews: the CHASE board ranks airports by live fog status, approach lighting, go-around height and flight time from your base. Forecast probabilities publish here per-airport once the calibrated model beats climatology on live verification — receipts on the scorecard. Methodology.

Sources: NOAA/NWS National Blend of Models guidance · METAR observations 2016–2026 (Iowa Environmental Mesonet) · FAA NASR. Machine access: data.json · llms.txt. Not for operational use.