{"icao":"KTYS","name":"McGhee Tyson Airport","lat":35.811,"lon":-83.994,"country":"US","tz":"America/New_York","updated":"2026-09-04T14:25Z","window":{"start":"2016-01-01","through":"2026-08-15"},"climatology":{"subCat1HoursPerYear":55,"bandDefinition":"visibility < ~800 m OR ceiling < 200 ft","fogSeasonPeakMonths":["January","December"],"monthlyHours":[12,6,3,1,3,2,1,3,4,6,5,10],"medianEventHours":2,"season":{"summary":"Fog season is January, February, March, May, August, September, October, November, December, peaking in January; fog is mostly a 3 AM\u20138 AM phenomenon; typically thinning out by 10 AM; a typical event lasts about 2 hours (local time, 10-year average).","months":["January","February","March","May","August","September","October","November","December"],"timeOfDay":"3 AM\u20138 AM","typicallyClearsBy":"10 AM"}},"forecast":{"covered":true,"public":false,"cycle":"2026-09-04T13:00:00Z","guidanceSignal":true,"wording":"NWS guidance shows a fog signal here in the next 48 hours. This station's calibrated percentages publish after live verification clears the accuracy bar. September typically brings about 4 hours of dense fog here."},"links":{"page":"https://fogatlas.org/fog/ktys/","liveForecastApi":"https://fogatlas.org/api/forecast","liveObservationsApi":"https://fogatlas.org/api/metar?ids=KTYS","hourlyClimatologyDetail":"https://fogatlas.org/data/detail/KTYS.json","verification":"https://fogatlas.org/fog/scorecard/","methodology":"https://fogatlas.org/#methodology"}}