{"city":"Chicago/Rockford","region":"US-IL","country":"US","slug":"chicago-rockford-il","updated":"2026-08-16T02:45Z","window":{"start":"2016-01-01","through":"2026-08-15"},"stations":[{"icao":"KRFD","name":"Chicago Rockford International Airport","subCat1HoursPerYear":37,"forecast":"live forecast"}],"primaryStation":"KRFD","forecast":{"covered":true,"public":true,"cycle":"2026-08-16T00:00:00Z","peakPct":31,"peakAtLocal":"2026-08-16T06:00:00-05:00","wording":"Some chance of fog: the calibrated forecast peaks at 31% (visibility under 1 mile) around 6 am Sunday."},"climatology":{"subCat1HoursPerYear":37,"fogSeasonPeakMonths":["December","January"],"medianEventHours":2,"season":{"summary":"Fog season runs November through March, peaking in December; fog is mostly a 4 AM\u20139 AM phenomenon; typically thinning out by 11 AM; a typical event lasts about 2 hours (local time, 10-year average).","months":["January","February","March","November","December"],"timeOfDay":"4 AM\u20139 AM","typicallyClearsBy":"11 AM"}},"links":{"page":"https://fogatlas.org/fog/city/chicago-rockford-il/","stationPages":["https://fogatlas.org/fog/krfd/"],"verification":"https://fogatlas.org/fog/scorecard/"}}