Thick Fog Forces FAA Ground-Delay Program at San Francisco International, Causing Nationwide Knock-On Delays

Morning commuters at San Francisco International Airport (SFO) faced delays of up to 82 minutes on December 8 after low clouds prompted the Federal Aviation Administration to initiate a ground-delay program limiting arrivals to 36 flights per hour. The measure—standard during low-visibility operations—held departing aircraft at origin airports, rippling through airline schedules across the United States and into Canada.



December is one of the heaviest corporate-travel months, and Bay-Area companies reported missed connections to East-Coast client meetings and trans-Pacific routes. Travel managers should monitor the National Airspace System Status site and consider earlier departures or remote-meeting contingency plans when tule fog is forecast. Meteorologists attribute the persistent fog to a ‘ridiculously resilient ridge’ of high pressure that is also delaying much-needed winter rain.

SFO averages more than 1,200 daily flights; capacity reductions of the scale imposed Monday can displace tens of thousands of passengers. Airlines issued change-fee waivers, but hotel and rebooking costs fall on travellers or employers. With similar foggy mornings expected all week, Bay-Area flyers are advised to book morning flights with buffer time or opt for Oakland or San Jose where visibility may be better.