KNHK — Patuxent River Naval Air Station (Trapnell Field)

fog forecast & climatology · Patuxent River city page · full 10-year analysis →
No fog signal in NWS guidance for the next 48 hours. dense fog (visibility under a mile) is rare here in September.forecast cycle 2026-09-04T13:00:00Z · page rebuilt daily · live layers below update hourly

Fog hours per year
28 h below CAT I minima (2016–2026 average)
Fog season
December and February
Typical fog event
~1 h once it forms (middle half 1–2 h, n=162)
Data through
2026-08-15 · machine-readable data.json

When this airport fogs in

In a typical year Patuxent River Naval Air Station (Trapnell Field) spends 28 hours below CAT I approach minima (visibility under ~½ mile or ceiling under 200 ft), concentrated in December and February. The strip above shows the hour-by-hour pattern for the current month from ten years of weather observations.

Fog season

January: ~4 hJanFebruary: ~6 hFebMarch: ~4 hMarApril: ~2 hAprMay: ~3 hMayJune: ~0 hJunJuly: ~0 hJulAugust: ~0 hAugSeptember: ~0 hSepOctober: ~1 hOctNovember: ~1 hNovDecember: ~7 hDec
Fog season runs December through May, peaking in December; fog is mostly a 6 AM–8 AM phenomenon; typically thinning out by 10 AM; a typical event lasts about 1 hour once it forms local time · 10-yr average

Runway infrastructure

endapproach lightsbest approachlengthRVR
025,021 ft
205,021 ft
06ALSF-1CAT I11,799 ft
2411,799 ft
149,732 ft
329,732 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.