KOSH — Wittman Regional Airport
fog forecast & climatology · Oshkosh city page · full 10-year analysis →
Fog unlikely through Saturday (peak 15%). September typically brings about 4 hours of dense fog here.forecast cycle 2026-09-04T13:00:00Z · page rebuilt daily · live layers below update hourly
- Fog hours per year
- 50 h below CAT I minima (2016–2026 average)
- Fog season
- January and December
- Typical fog event
- ~1 h once it forms (middle half 1–3 h, n=218)
- Data through
- 2026-08-15 · machine-readable data.json
When this airport fogs in
In a typical year Wittman Regional Airport spends 50 hours below CAT I approach minima (visibility under ~½ mile or ceiling under 200 ft), concentrated in January and December. The strip above shows the hour-by-hour pattern for the current month from ten years of weather observations.
Fog season
Fog season is January, February, March, April, September, November, December, peaking in January; fog is mostly a 3 AM–10 AM phenomenon; typically thinning out by noon; a typical event lasts about 1 hour once it forms local time · 10-yr average
Runway infrastructure
| end | approach lights | best approach | length | RVR |
|---|---|---|---|---|
| 05 | — | — | 3,424 ft | — |
| 23 | — | — | 3,424 ft | — |
| 09 | — | LPV | 6,179 ft | — |
| 27 | — | LPV | 6,179 ft | — |
| 13 | — | — | 3,061 ft | — |
| 31 | — | — | 3,061 ft | — |
| 18 | — | LPV | 8,002 ft | RVR |
| 36 | MALSR | CAT I | 8,002 ft | RVR |
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.