On August 18, 2026, the FAA held 17 airports in the United States under 26 delay programs in total, with Seattle-Tacoma International Airport (SEA) experiencing the highest peak delay of 151 minutes. These figures come from a full day aggregation of the FAA’s official delay feed, tracked by travelandtournews.com.
Duration and Type of FAA Delay Programs Across Airports
The delay programs included eight Ground Stop programs, six Ground Delay programs, and twelve General Arrival/Departure Delay infos. A ground stop holds departures bound for an airport on the ground at their origin, while a ground delay program meters arrivals by assigning later departure times.
Program durations varied widely. The longest was a General Arrival/Departure Delay Info at Newark Liberty International (EWR) lasting 22 hours 20 minutes, which saw average delays peak at 106 minutes. Other extended Ground Delay programs included San Diego International (SAN) for 18 hours 40 minutes with peak average delays of 31 minutes, and San Francisco
International (SFO) running Ground Delay programs for 5 hours 40 minutes with peak averages of 42 minutes.
Ground Stop programs were shorter but immediate, for example, the worst-hit airport Teterboro Airport (TEB) had a Ground Stop lasting 1 hour 40 minutes for thunderstorms, although with no delay minutes recorded. Similar short Ground Stops occurred at LaGuardia (LGA) and Philadelphia International (PHL), both lasting 1 hour 20 minutes also for thunderstorms.
| Airport | FAA programme | Cause | Peak average delay | In force (UTC) |
|---|---|---|---|---|
| TEB | Ground Stop Programs | thunderstorms | – | 00:00 to 01:40 (1 hour 40 minutes) |
| LaGuardia (LGA) | Ground Stop Programs | thunderstorms | – | 00:00 to 01:20 (1 hour 20 minutes) |
| Philadelphia International (PHL) | Ground Stop Programs | thunderstorms | – | 00:00 to 01:20 (1 hour 20 minutes) |
| Boston Logan International (BOS) | Ground Stop Programs | low ceilings | – | 17:20 to 18:20 (1 hour) |
| Newark Liberty International (EWR) | Ground Stop Programs | thunderstorms | – | 00:00 to 00:40 (40 minutes) |
| Ronald Reagan Washington National (DCA) | Ground Stop Programs | thunderstorms | – | 00:00 to 00:20 (20 minutes) |
| John F. Kennedy International (JFK) | Ground Stop Programs | thunderstorms | – | 01:20 to 01:40 (20 minutes) |
| Seattle-Tacoma International (SEA) | Ground Stop Programs | low visibility | – | 15:20 to 15:40 (20 minutes) |
| YYZ | Ground Delay Programs | other | 80 min | 00:00 to 02:20 (2 hours 20 minutes) |
| Boston Logan International (BOS) | Ground Delay Programs | low ceilings | 75 min | 00:00 to 00:20 (20 minutes) |
| Seattle-Tacoma International (SEA) | Ground Delay Programs | low visibility | 55 min | 16:00 to 18:20 (2 hours 20 minutes) |
| San Francisco International (SFO) | Ground Delay Programs | low ceilings | 42 min | 12:40 to 18:20 (5 hours 40 minutes) |
| Ronald Reagan Washington National (DCA) | Ground Delay Programs | other | 32 min | 00:00 to 02:20 (2 hours 20 minutes) |
| San Diego International (SAN) | Ground Delay Programs | airport volume | 31 min | 00:00 to 18:40 (18 hours 40 minutes) |
Thunderstorms and Weather Were the Leading Causes of Delays
The FAA’s stated reasons for the programs centered on weather and volume issues. Thunderstorms accounted for eight Ground Stop programs on the morning of August 18 at airports including TEB,
LGA, PHL, EWR, DCA, and JFK. Other weather-related causes included low ceilings driving four Ground Stop and Ground Delay programs at Boston Logan International (BOS) and low visibility triggering Ground Stop and Ground Delay programs at Seattle.
Other top reasons for delay programs included airport volume, linked to the lengthy Ground Delay at San Diego International, and Traffic Management Initiatives related to swaps and metering due to weather or volume constraints. These TM initiatives affected airports such as EWR, LGA, and IAD, spanning several hours each with peak delays exceeding one hour on average.
Comparison with Previous Days Shows Slight Decrease in Delay Programs
Compared to the previous day, the
number of delay programs fell from 29 to 26, a decrease of three programs. The number of airports affected dropped from 20 to 17, aligning closely with the recent seven-day average of 17.7 airports. The peak average delay of 106 minutes matched high delays seen at Newark and LaGuardia, though these were not the worst in the recent tracking window.
This analysis is based on FAA data tracked by travelandtournews.com, sampling every 20 minutes from midnight to 22:20 UTC on August 18, 2026.
Methodology. travelandtournews.com samples the FAA’s National Airspace System status feed every 20 minutes throughout the US operating
day and aggregates the result. This report is built from 68 samples taken between 00:00 and 22:20 UTC on 2026-08-18. Durations are the observed window between the first and last sample in which a programme was in force, so a programme’s true length may be slightly longer than shown. Ground stops, ground delay programmes, airport closures and general delays are all published by the FAA in real time; the daily aggregation is ours.
