SFO Delays Snarl Travel for Hundreds Across Airline Networks

Hundreds of travelers faced significant disruption at San Francisco International Airport on May 28 and 29 as weather-related ground delay programs contributed to 285 delayed flights and at least five cancellations, affecting passengers on SAS, United, Delta Air Lines and several other major carriers across the United States and beyond.

Weather and Capacity Constraints Converge at SFO

Publicly available information from aviation trackers and local coverage indicates that low clouds, shifting winds and reduced arrival capacity at San Francisco International Airport have forced air traffic managers to meter inbound flights, slowing the operation throughout Thursday and into Friday. Ground delay programs limited the number of arrivals per hour, pushing back departure times and contributing to rolling congestion across the schedule.

Average delays for some arrival periods reportedly approached one to three hours, with late-morning and afternoon banks particularly hard hit. As aircraft arrived late into San Francisco, crews and planes scheduled for subsequent legs departed behind schedule, amplifying disruption for passengers connecting onward to destinations across North America, Europe and Asia.

San Francisco’s location along the Bay and its intersecting runway configuration make it especially vulnerable to low ceilings and wind shifts. When visibility drops or crosswinds rise beyond certain thresholds, the airport often reduces simultaneous operations, a step that tends to generate knock-on delays even when actual storm conditions appear relatively mild to travelers watching from the terminal windows.

The pattern observed this week aligns with longer-term trends at SFO, where fog and marine-layer cloud cover have a seasonal impact on on-time performance. Ground delay programs of varying intensity have become a regular feature of late spring operations, particularly during early morning and late evening periods when the low cloud deck is slow to clear.

Network Impact on SAS, United, Delta and Partner Airlines

The delays at San Francisco did not remain a local issue. Flight status boards and tracking tools show that at least 285 flights connected to SFO experienced significant schedule disruption, while five were cancelled outright. United Airlines, the largest carrier at the airport, accounted for a substantial share of the delayed departures and arrivals as its hub schedule absorbed the impact of the reduced capacity.

Delta Air Lines, which operates transcontinental services linking SFO with key domestic hubs, also reported a series of delayed operations, particularly on early morning and evening routes. Disruption on these flights can strand connecting passengers in intermediate hubs and compress turnaround times for aircraft assigned to overnight and early next-day services.

Long-haul and alliance partners were similarly affected. According to published airline news coverage, travelers booked on Scandinavian carrier SAS facing connections through US gateways saw their itineraries complicated as SFO-related disruption cascaded into broader network adjustments. Passengers headed to and from European and Canadian cities on partner airlines, including services to Copenhagen and Toronto, encountered extended ground holds and revised departure times.

Regional affiliates and codeshare operators feeding traffic into SFO, such as SkyWest-operated flights for major carriers, also played a role in the day’s statistics. When smaller regional jets arrive late or depart out of sequence, banked hub operations lose efficiency, further contributing to the headline delay count and increasing the risk of missed onward connections.

Passenger Experience in Terminals and Across the System

Inside the terminals, the numbers translated into crowded gate areas, long lines at customer service counters and frequent gate change announcements. Travelers on affected flights reported multi-hour waits as departure times were successively revised in response to evolving air traffic control programs and shifting weather conditions over the Bay Area.

Because ground delay programs for San Francisco often hold flights at their origin city rather than stacking them near the airport, many passengers first felt the impact far from California. Departures bound for SFO from East Coast and Midwest airports left the gate late, compressing connection windows and forcing some travelers into overnight stays when misaligned schedules could not be recovered.

The disruption reached beyond point-to-point domestic routes. International passengers connecting through San Francisco, including those on itineraries touching Europe and Asia, faced complex rebookings. Fixed departure slots for long-haul services and limited daily frequencies meant that a missed connection could translate into a wait of many hours or even until the following day.

Travel forums and social media posts referenced a familiar scene at SFO during weather-related slowdowns: full flights, limited spare seats for reaccommodation and travelers searching for power outlets and quiet corners as they waited for new boarding times. For some, travel insurance and flexible tickets softened the blow; for others, out-of-pocket expenses for hotels and meals added frustration to an already difficult travel day.

Why San Francisco Is Prone to Recurring Disruption

Aviation analysts frequently highlight San Francisco International as an airport where small shifts in weather can have outsized operational effects. The combination of high demand, a hub-and-spoke structure for several carriers and geographically constrained runway approaches leaves little margin for error when conditions deteriorate or winds change direction.

Historical performance data and previous Federal Aviation Administration planning documents describe SFO as operating near capacity during peak waves of arrivals and departures. When air traffic managers need to increase spacing between arriving aircraft, the effective capacity of the airfield drops, and airlines must adjust by delaying or rerouting flights to avoid airborne congestion.

Unlike some inland hubs that can absorb weather by temporarily holding aircraft on taxiways or in nearby holding stacks, SFO’s proximity to complex coastal airspace makes prolonged airborne holding less practical. As a result, delay management tends to occur at departure airports, leaving travelers waiting at gates hundreds or thousands of miles away for clearance to push back.

These structural characteristics, combined with the seasonal prevalence of fog and marine layer clouds along the Northern California coast, mean that even routine weather can produce cascading delays. Industry observers often advise travelers connecting through San Francisco during these periods to anticipate potential disruption and plan itineraries accordingly.

What Travelers Can Do During Ongoing Delays

Consumer guidance derived from airline and passenger advocacy resources emphasizes that preparation can meaningfully reduce the stress of events like the latest disruptions at SFO. Travelers booked through weather-prone hubs are encouraged to select longer connection times, particularly when itineraries involve international legs or the final flights of the day into regional airports.

During active ground delay programs, regularly checking airline apps and airport information screens can provide earlier notice of schedule changes than waiting for public address announcements alone. Same-day change options, where available, may allow passengers to reroute through alternative hubs or shift to earlier or later departures that are less affected by congestion.

Reports from recent disruption events also underline the value of understanding an airline’s rebooking and compensation policies. While weather-related delays in the United States generally limit eligibility for financial compensation, some carriers provide meal vouchers, hotel discounts or complimentary rebooking when delays reach certain thresholds or stretch into the overnight hours.

As San Francisco International works through the latest wave of delays and cancellations, travelers across the network continue to feel the effects. With airlines such as SAS, United and Delta Air Lines adjusting schedules and repositioning aircraft to restore normal operations, residual delays are likely to persist even after weather conditions over the Bay Area improve.