Dense Fog Delays Flights at San Diego International Airport

(SAN DIEGO, CALIFORNIA) Dense fog forced the Federal Aviation Administration to issue a morning ground stop at San Diego International Airport on Tuesday, October 21, 2025, halting inbound flights as low clouds cut visibility across the runway approaches.

The FAA began the ground stop at about 7:22 a.m. Pacific Time and lifted it around 9:00 a.m., officials said, but ripple effects continued with average departure delays of roughly 31 minutes through the late morning as airlines worked through backlogs.

Recent delay patterns and timeline

Airport data from recent days shows a pattern of repeated morning disruption:

• On Monday, October 20, more than 90 flights were delayed and at least 2 were cancelled, with Southwest Airlines responsible for more than half of those delays.
• On Friday, October 17, the week’s most severe disruption occurred: at least 100 flights were delayed and 4 were cancelled after a ground stop that lasted from 7:28 a.m. until noon.
• Many flights slipped by 15–30 minutes, while some passengers waited up to 4 hours to depart or meet arriving family.

Officials said the main cause was weather—specifically dense fog and low visibility—though some flights also faced knock-on issues from mechanical checks and delays at other airports. The FAA’s tool that assigns arrival spacing during low-visibility operations remained active for parts of each affected morning, stretching the schedule as pilots and air traffic controllers kept wider gaps between planes.

Why fog causes ground stops and lasting delays

San Diego’s fall and winter months often bring patchy coastal fog that burns off slowly after sunrise. Airport and weather briefings indicate this seasonal pattern will continue, with the National Weather Service cautioning about morning and evening fog that could reduce visibility below safe approach standards on any given day.

When the ceiling—the cloud height above ground—drops too low, controllers can’t safely land as many planes per hour. That’s when a ground stop, which pauses arrivals from other airports, becomes likely.

For example:

1. A ground stop pauses inbound flights.
2. When lifted, the backlog of arrivals and departures converges into the same time windows.
3. Taxiways and gates become congested, creating additional delays.
4. Airlines must rebalance crews and aircraft, causing further schedule ripple effects.

When the ceiling remains below instrument landing minima, arrivals must hold or divert. Once the fog lifts, airlines face the challenge of rebalancing crews and aircraft already off their planned rotations.

Traveler impacts and immigration-specific concerns

The practical impact on travelers is uneven but real, especially during the early-morning push when many departures and inbound flights overlap.

• A 90-minute ground stop can push the first wave of arrivals into mid-morning flights, creating queues on taxiways and at gates.
• Delays often persist even after the FAA lifts the restriction because ramp operations and gate availability take time to recover.

From an immigration and time-sensitive appointments perspective:

• People flying to consular appointments, biometrics, or court dates often book early departures to arrive the same day. Dense fog can push those flights back and cause missed interviews or hearings that are difficult to reschedule.
• New arrivals may face compressed connection times to domestic destinations, increasing the risk of overnight stays or missed reporting deadlines set by schools or employers.

Recommended precautions for time-sensitive travel during fog season:

• Book longer connection windows in the morning.
• Avoid tight same-day connections after overnight international flights into San Diego.
• Build in buffer days for appointments when possible.
• Keep contact details for consulates, attorneys, and employers handy to document and report weather-related delays.

According to analysis by VisaVerge.com, weather-related disruptions at coastal airports like San Diego can cluster across several mornings in a single week during peak fog periods. Recent events—Friday’s hours-long ground stop, Monday’s widespread delays, and Tuesday’s shorter but disruptive ground stop—fit this pattern.

What officials and airlines are advising

Airport and FAA officials emphasized that safety procedures during low visibility work as designed, but they reduce capacity. With arrivals spaced out, even small timing shifts can snowball.

Airline responses typically include:

• Swapping aircraft to keep longer routes moving while shorter hops wait.
• Consolidating lightly booked flights.
• Offering fee waivers in some cases when weather creates widespread disruption.

Some passengers on Monday reported 15–30 minute holds at the gate even after boarding, as ramp operations moved cautiously in poor visibility and crews waited for new takeoff slots. Others faced longer waits while aircraft that had diverted Friday morning returned to San Diego after the fog cleared.

Practical impacts highlighted:

• Travelers with checked bags and international connections faced added pressure if Customs processing stacked onto late arrivals.
• Families meeting elderly relatives or unaccompanied minors had to adjust pickup plans on short notice.
• Workers on tight schedules risk missed childcare pickups and lost wages.

The FAA recommends keeping an eye on national advisories whenever weather threatens to disrupt multiple airports. The agency’s real-time dashboard, the FAA National Airspace System Status, shows active ground stops and arrival spacing programs. When San Diego appears in yellow or red on that map during the morning peak, passengers should expect slower operations and possible cancellations that extend into midday.

San Diego International Airport also noted that fog events can lift unevenly across the airfield—one runway end may clear before the other—which affects approach paths and the number of arrivals per hour. Ground crews need workable visibility to move equipment, service aircraft, and guide planes to gates. Even after flight operations resume, ramp safety rules may keep traffic slower than normal until conditions stabilize.

Practical tips and airport guidance

Airport staff continue to urge practical steps for the coming weeks:

• Allow extra time to reach the airport when low clouds are in the forecast.
• Keep phone notifications on for airline messages about gate changes or rebooking options.
• Check flight status right before leaving home and again upon arrival at the terminal. Use the airport’s online board or the San Diego International Airport flight status page for real-time updates.

While the latest ground stop on Tuesday was shorter than Friday’s event, the spread of delays shows how quickly fog can upend a morning schedule at a single-runway airport like San Diego. With more patchy fog expected, airlines and passengers are likely to face more of these stop-and-go mornings.

The airport’s advice remains steady: plan for delays when the forecast calls for low ceilings, and build in extra time where you can.