KSUX — Sioux Gateway Airport / Brigadier General Bud Day Field

fog forecast & climatology · Sioux City city page · full 10-year analysis →
Fog unlikely through Saturday (peak 2%). 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
49 h below CAT I minima (2016–2026 average)
Fog season
December and January
Typical fog event
~1 h once it forms (middle half 1–3 h, n=226)
Data through
2026-08-15 · machine-readable data.json

When this airport fogs in

In a typical year Sioux Gateway Airport / Brigadier General Bud Day Field spends 49 hours below CAT I approach minima (visibility under ~½ mile or ceiling under 200 ft), concentrated in December and January. The strip above shows the hour-by-hour pattern for the current month from ten years of weather observations.

Fog season

January: ~10 hJanFebruary: ~6 hFebMarch: ~4 hMarApril: ~2 hAprMay: ~1 hMayJune: ~1 hJunJuly: ~4 hJulAugust: ~6 hAugSeptember: ~1 hSepOctober: ~3 hOctNovember: ~2 hNovDecember: ~11 hDec
Fog season is January, February, March, July, August, October, December, peaking in December; fog is mostly a 2 AM–9 AM phenomenon; typically thinning out by 11 AM; a typical event lasts about 1 hour once it forms local time · 10-yr average

Runway infrastructure

endapproach lightsbest approachlengthRVR
13MALSCAT I9,002 ftRVR
31MALSRCAT I9,002 ftRVR
18LPV6,401 ft
36LPV6,401 ft

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.