FlyerIntel Research
Airports Where Weather Hurts Reliability Most
Every airport blames the weather. The data shows how much of the delay it actually explains.
Published August 30, 2026 · Source period July 2023 – July 2026
Summary
Across 64 major US airports, weather accounts for 5.1% of reported delay minutes on average, far less than most travelers assume. The spread is wide: at ABE (Allentown) weather explains 9.8% of delay minutes, against 1.3% at SJU (San Juan). The larger cause almost everywhere is a late inbound aircraft: disruption inherited from earlier in the day rather than created at the airport.
Key findings
- ABE is the most weather-affected major airport, with 9.8% of delay minutes attributed to weather.
- SJU is the least affected, at 1.3%.
- The average across major airports is 5.1%. Weather is rarely the largest single cause.
- Late-arriving aircraft accounts for 41.0% of delay minutes on average, the largest category at most airports.
What "weather delay" actually counts
The DOT splits reported delay minutes into five causes, and weather appears in two of them. The weather category counts only extreme conditions that prevented operation directly. Weather that closes airspace or slows the arrival flow is recorded under the national airspace system category instead, alongside congestion and air traffic control. The figures below use the narrow definition, which is why they look lower than intuition suggests and why the airspace column belongs next to them.
Delay causes by airport
| Airport | City | Weather | Airspace | Carrier | Late aircraft | On time | Summer drop |
|---|---|---|---|---|---|---|---|
| ABE | Allentown | 9.8% | 15.3% | 39.7% | 35.1% | 82.8% | 6.7 pts |
| ILM | Wilmington | 9.7% | 18.4% | 29.2% | 42.7% | 81.7% | 7.3 pts |
| IAD | Washington | 9.3% | 25.0% | 32.8% | 32.8% | 81.0% | 8.7 pts |
| MSP | Minneapolis | 8.5% | 21.3% | 50.0% | 20.2% | 81.1% | 8.5 pts |
| ORD | Chicago | 8.3% | 20.4% | 30.6% | 40.6% | 74.5% | 7.6 pts |
| OMA | Omaha | 8.3% | 20.3% | 34.7% | 36.6% | 81.7% | 6.5 pts |
| DFW | Dallas–Fort Worth | 8.2% | 14.0% | 31.2% | 46.5% | 73.1% | 7.4 pts |
| DTW | Detroit | 7.8% | 20.8% | 50.7% | 20.5% | 79.6% | 7.6 pts |
| IAH | Houston | 7.6% | 20.1% | 33.5% | 38.7% | 77.4% | 8.4 pts |
| CLT | Charlotte | 7.5% | 15.1% | 30.0% | 47.0% | 74.8% | 9.8 pts |
| MEM | Memphis | 7.2% | 19.5% | 36.1% | 37.1% | 81.2% | 6.2 pts |
| TUS | Tucson | 7.2% | 19.5% | 38.0% | 35.1% | 84.3% | 3.2 pts |
| SBA | Santa Barbara | 6.9% | 26.5% | 28.0% | 38.5% | 82.2% | 1.8 pts |
| MCO | Orlando | 6.6% | 23.0% | 28.9% | 41.2% | 74.8% | 10.8 pts |
| SLC | Salt Lake City | 6.4% | 18.7% | 48.3% | 26.6% | 84.0% | 4.9 pts |
| ANC | Anchorage | 6.2% | 14.5% | 42.2% | 37.0% | 83.6% | 5.8 pts |
| MKE | Milwaukee | 6.1% | 20.3% | 40.2% | 33.3% | 80.7% | 5.1 pts |
| ATL | Atlanta | 6.0% | 20.4% | 43.8% | 29.6% | 78.7% | 8.0 pts |
| MIA | Miami | 6.0% | 20.6% | 32.6% | 40.6% | 73.2% | 10.1 pts |
| DCA | Washington | 5.8% | 19.3% | 26.1% | 48.7% | 76.5% | 7.1 pts |
| MYR | Myrtle Beach | 5.7% | 21.2% | 24.9% | 48.2% | 80.6% | 9.7 pts |
| MCI | Kansas City | 5.6% | 21.1% | 29.0% | 44.1% | 81.0% | 5.3 pts |
| SAT | San Antonio | 5.6% | 18.9% | 30.8% | 44.6% | 82.3% | 4.9 pts |
| HOU | Houston | 5.5% | 17.1% | 30.7% | 46.4% | 78.8% | 5.8 pts |
| EWR | Newark | 5.4% | 25.7% | 28.4% | 40.4% | 77.7% | 7.8 pts |
| PHL | Philadelphia | 5.3% | 21.0% | 30.0% | 43.6% | 76.2% | 10.2 pts |
| SEA | Seattle | 5.2% | 22.4% | 42.1% | 30.0% | 79.1% | 7.1 pts |
| JAX | Jacksonville | 5.0% | 18.0% | 32.1% | 44.9% | 80.0% | 8.7 pts |
| AUS | Austin | 5.0% | 17.8% | 32.7% | 44.4% | 78.0% | 4.5 pts |
| IND | Indianapolis | 5.0% | 27.7% | 28.9% | 38.3% | 81.9% | 5.3 pts |
| MSY | New Orleans | 5.0% | 19.6% | 28.5% | 46.7% | 78.7% | 6.6 pts |
| ABQ | Albuquerque | 4.7% | 18.3% | 32.8% | 44.1% | 83.2% | 4.1 pts |
| PIT | Pittsburgh | 4.7% | 29.1% | 28.5% | 37.6% | 82.1% | 6.4 pts |
| LGA | New York | 4.6% | 26.3% | 28.2% | 40.7% | 78.3% | 6.4 pts |
| DEN | Denver | 4.5% | 18.1% | 33.2% | 44.1% | 76.0% | 9.9 pts |
| FLL | Fort Lauderdale | 4.5% | 25.1% | 31.3% | 38.5% | 72.6% | 8.5 pts |
| BWI | Baltimore | 4.4% | 20.7% | 34.6% | 39.9% | 76.0% | 10.6 pts |
| SAN | San Diego | 4.4% | 22.3% | 26.1% | 47.1% | 77.9% | 5.4 pts |
| BUF | Buffalo | 4.3% | 22.9% | 29.3% | 43.4% | 79.4% | 8.9 pts |
| BNA | Nashville | 4.2% | 20.0% | 29.3% | 46.3% | 78.3% | 6.2 pts |
| TPA | Tampa | 4.1% | 21.2% | 26.3% | 48.3% | 78.2% | 8.3 pts |
| CMH | Columbus | 4.1% | 27.4% | 30.8% | 37.7% | 82.1% | 4.7 pts |
| STL | St. Louis | 4.0% | 19.2% | 30.8% | 45.8% | 79.1% | 7.0 pts |
| MDW | Chicago | 4.0% | 18.9% | 33.0% | 43.8% | 76.4% | 9.9 pts |
| RDU | Raleigh–Durham | 4.0% | 24.1% | 28.0% | 43.9% | 79.4% | 7.4 pts |
| DAL | Dallas | 3.9% | 16.4% | 29.4% | 50.2% | 76.0% | 4.8 pts |
| SNA | Santa Ana | 3.8% | 22.7% | 31.4% | 41.9% | 82.2% | 4.3 pts |
| RSW | Fort Myers | 3.8% | 21.7% | 25.5% | 48.9% | 78.8% | 7.5 pts |
| CLE | Cleveland | 3.8% | 26.2% | 30.7% | 39.2% | 80.9% | 6.9 pts |
| JFK | New York | 3.5% | 26.8% | 37.4% | 32.1% | 77.0% | 9.1 pts |
| PDX | Portland | 3.4% | 22.8% | 35.5% | 38.0% | 83.2% | 5.0 pts |
| BUR | Burbank | 3.4% | 25.5% | 22.4% | 48.6% | 82.8% | 1.5 pts |
| CHS | Charleston | 3.3% | 22.6% | 29.5% | 44.6% | 80.6% | 5.3 pts |
| SFO | San Francisco | 3.1% | 20.6% | 31.1% | 45.1% | 78.7% | 4.0 pts |
| BOS | Boston | 3.0% | 25.8% | 32.7% | 38.4% | 77.2% | 5.7 pts |
| SMF | Sacramento | 2.8% | 16.8% | 34.2% | 46.0% | 83.2% | 4.0 pts |
| LAS | Las Vegas | 2.8% | 19.1% | 34.2% | 43.8% | 78.0% | 5.9 pts |
| LAX | Los Angeles | 2.7% | 20.6% | 38.7% | 37.8% | 81.4% | 4.9 pts |
| SJC | San Jose | 2.6% | 19.6% | 31.6% | 46.0% | 84.1% | 3.9 pts |
| PHX | Phoenix | 2.4% | 15.0% | 37.6% | 44.8% | 80.3% | 5.4 pts |
| HNL | Honolulu | 2.2% | 7.4% | 54.2% | 35.7% | 85.3% | 0.7 pts |
| ONT | Ontario | 2.2% | 19.4% | 33.3% | 45.0% | 83.5% | 3.6 pts |
| OAK | Oakland | 1.4% | 16.1% | 35.4% | 46.8% | 82.0% | 4.8 pts |
| SJU | San Juan | 1.3% | 14.3% | 36.5% | 47.8% | 76.2% | 8.0 pts |
Shares are of total reported delay minutes, which the DOT collects only for arrivals 15 or more minutes late.
Geography is not destiny
Airports with similar climates land in very different places on this table, which is the useful part. An airport with runway capacity to spare absorbs a weather event; one already running at its limit converts the same event into a cascade that lasts the rest of the day and gets recorded, hours later and hundreds of miles away, as a late-arriving aircraft rather than as weather at all.
Pages for what this report covers
Methodology
Calculated by FlyerIntel from 21,708,321 individual flight records in the US Department of Transportation Bureau of Transportation Statistics Reporting Carrier On-Time Performance dataset, covering July 2023 through July 2026. Following BTS methodology, a flight counts as delayed when it arrives 15 or more minutes after its scheduled arrival time. Cancelled and diverted flights have no arrival time and are excluded from on-time rates rather than counted as late; cancellation rates are reported separately. Full definitions are published at /methodology/. Delay-cause shares are computed from the DOT’s five reported cause categories as a proportion of total reported delay minutes for departures at each airport. Summer drop is the difference between mean on-time rate in April, May, September and October and in June, July and August.
Limitations
The source dataset covers scheduled domestic flights operated by carriers above the DOT reporting threshold; smaller carriers and international flights are not included. Flights sold under a mainline brand but flown by a regional carrier are attributed to the operating carrier, which is how the DOT records them. Past performance describes what has happened and is not a prediction about any individual flight. Cause minutes are reported by the operating carrier and only for arrivals 15 or more minutes late, so these shares describe delayed flights rather than all flights. The boundary between the weather and airspace categories is a reporting convention, not a physical one.
Sources
- FlyerIntel analysis — FlyerIntel · source
- Reporting Carrier On-Time Performance — US Department of Transportation, Bureau of Transportation Statistics · source
Full FlyerIntel methodology · Report a problem with this analysis