US airport delays

What is disrupted right now, from the FAA's live status feed, and how often flights actually ran late, from the Department of Transportation's flight-by-flight records, which arrive about two to three months after the month ends. Back to World Pulse.

Live now — FAA · checked 20:15 UTC

BOS · Ground delay program
avg 148 min, max 399 min · runway construction
since 11-07 13:00 UTC (first seen)
LGA · Ground stop
· wind
since 11-07 19:30 UTC (first seen)
4 closure / restriction notices (mostly NOTAMs limiting some aircraft)
SNAClosure!SNA 11/003 SNA AD AP CLSD DLY 0730-1415 2611030730-2611081415
LASRestricted (NOTAM)!LAS 10/160 LAS AD AP CLSD TO NON SKED TRANSIENT GA ACFT EXC 24HR PPR 702-261-7775 2610281926-2701272300
LAXRestricted (NOTAM)!LAX 05/277 LAX AD AP CLSD TO NON SKED TRANSIENT GA ACFT EXC 24HR PPR CTC ATLANTIC AVIATION 310-258-9884 OR SIGNATURE AVIATION 310-410-9605 2605271826-2705281600
SANRestricted (NOTAM)!SAN 10/004 SAN AD AP CLSD TO NON SKED TRANSIENT GA ACFT EXC PPR 619-298-7704 2610011633-2701010800
Month Aug 2026 Jul 2026 Jun 2026 May 2026 Apr 2026 Mar 2026 Feb 2026 Jan 2026 Dec 2025 Nov 2025 Oct 2025 Sep 2025 Aug 2025 Measure Departures Arrivals
15%45%+ of arrivals 15+ min late dot size = flights · ring = FAA program live now

Nationally, February 2025

20.8%
of 496,476 arrivals ran 15+ min late · usual for February: 18.9% · 1.5% cancelled
Last 37 months · dashed = usual for that month (median of up to 5 earlier years, 2020 left out)
Where late-arrival minutes came from
Late aircraft 37%
Airline 34%
Air traffic 22%
Weather 7%
Security 0%

Airports, February 2025 (arrivals)

AirportCityFlightsLate 15+ vs usual CancelledAvg minMain cause
DFW Dallas/Fort Worth, TX 22,857 20.3% -0.8 1.5% 18 Airline
DEN Denver, CO 22,808 20.6% +0.5 0.8% 16 Late aircraft
ATL Atlanta, GA 22,638 19.3% +6.5 0.5% 15 Airline
ORD Chicago, IL 19,982 21.3% +2.8 1.3% 18 Late aircraft
CLT Charlotte, NC 15,608 19.8% +5.4 3.2% 18 Late aircraft
PHX Phoenix, AZ 15,459 16.2% -1.6 0.6% 13 Airline
LAS Las Vegas, NV 14,180 20.2% -2.0 0.9% 15 Air traffic
LAX Los Angeles, CA 13,783 18.6% -1.1 0.7% 14 Airline
MCO Orlando, FL 12,573 21.3% +0.4 1.0% 16 Late aircraft
DCA Washington, DC 10,988 41.3% +25.5 7.5% 37 Air traffic
SEA Seattle, WA 10,730 20.8% +2.8 1.4% 13 Airline
BOS Boston, MA 10,296 22.0% +1.0 2.5% 18 Late aircraft
LGA New York, NY 10,053 20.5% -1.6 2.5% 17 Airline
SFO San Francisco, CA 9,939 26.9% +4.0 1.2% 20 Air traffic
MIA Miami, FL 9,448 20.9% +2.4 0.9% 17 Airline
EWR Newark, NJ 9,400 19.8% -1.4 1.3% 16 Air traffic
SLC Salt Lake City, UT 8,789 17.3% +4.2 0.4% 13 Airline
DTW Detroit, MI 8,587 20.6% +4.8 0.9% 17 Airline
IAH Houston, TX 8,461 18.0% -0.0 0.5% 13 Late aircraft
JFK New York, NY 7,853 20.3% +1.0 2.0% 17 Late aircraft
MSP Minneapolis, MN 7,766 17.2% +2.3 0.6% 14 Airline
FLL Fort Lauderdale, FL 7,383 22.1% +0.4 1.1% 17 Air traffic
BNA Nashville, TN 6,909 18.5% +2.5 1.5% 13 Late aircraft
SAN San Diego, CA 6,606 23.4% +3.4 0.9% 13 Late aircraft
BWI Baltimore, MD 6,568 15.1% +1.9 0.8% 10 Late aircraft
PHL Philadelphia, PA 6,359 21.5% +4.9 3.5% 20 Late aircraft
TPA Tampa, FL 6,306 22.7% +4.1 0.9% 16 Late aircraft
AUS Austin, TX 5,843 18.2% -1.5 0.4% 12 Late aircraft
DAL Dallas, TX 5,343 14.6% +0.7 0.4% 9 Late aircraft
MDW Chicago, IL 4,744 15.7% +3.3 0.8% 11 Late aircraft
HNL Honolulu, HI 4,638 16.5% -3.7 0.3% 10 Airline
MSY New Orleans, LA 4,439 23.1% +5.0 0.5% 15 Late aircraft
STL St. Louis, MO 4,418 15.8% +0.3 1.0% 11 Late aircraft
PDX Portland, OR 3,981 19.3% +2.2 1.7% 12 Late aircraft
SMF Sacramento, CA 3,975 16.3% -0.5 0.5% 10 Late aircraft
HOU Houston, TX 3,884 15.5% +1.1 0.4% 8 Late aircraft
RDU Raleigh/Durham, NC 3,848 19.4% +2.1 2.3% 14 Late aircraft
IAD Washington, DC 3,744 16.7% +1.6 0.9% 13 Late aircraft
RSW Fort Myers, FL 3,536 23.8% +2.6 1.2% 17 Late aircraft
SJC San Jose, CA 3,465 15.2% -1.2 0.7% 9 Late aircraft
MCI Kansas City, MO 3,367 19.9% +1.1 0.7% 13 Late aircraft
IND Indianapolis, IN 3,299 19.7% +3.8 1.3% 13 Late aircraft
SNA Santa Ana, CA 3,186 16.9% +0.2 1.1% 10 Airline
CMH Columbus, OH 3,103 20.5% +4.1 1.4% 14 Late aircraft
PIT Pittsburgh, PA 2,939 20.3% +5.9 1.7% 15 Late aircraft
SAT San Antonio, TX 2,922 18.7% -1.1 0.3% 12 Late aircraft
SJU San Juan, PR 2,895 23.8% +1.2 0.7% 17 Airline
PBI West Palm Beach/Palm Beach, FL 2,855 30.4% +7.8 1.5% 24 Air traffic
CLE Cleveland, OH 2,789 20.0% +1.9 2.1% 16 Late aircraft
OAK Oakland, CA 2,671 13.7% -4.0 0.7% 8 Late aircraft
CVG Cincinnati, OH 2,324 23.0% +6.4 1.5% 16 Late aircraft
BUR Burbank, CA 2,183 15.8% -1.4 1.6% 10 Late aircraft
JAX Jacksonville, FL 2,098 22.9% +4.6 1.0% 15 Late aircraft
OGG Kahului, HI 1,999 12.9% -6.4 0.7% 8 Airline
MKE Milwaukee, WI 1,796 23.5% +3.9 1.2% 18 Airline
ONT Ontario, CA 1,773 16.6% +0.0 0.9% 10 Late aircraft
OMA Omaha, NE 1,755 19.7% -0.0 0.6% 13 Airline
TUS Tucson, AZ 1,755 18.7% -0.3 0.5% 12 Airline
BDL Hartford, CT 1,700 19.2% -0.6 2.2% 16 Late aircraft
ABQ Albuquerque, NM 1,693 15.6% -4.7 0.4% 10 Late aircraft
BOI Boise, ID 1,683 21.8% +6.0 0.5% 13 Late aircraft
OKC Oklahoma City, OK 1,653 21.5% +0.9 2.4% 17 Airline
SRQ Sarasota/Bradenton, FL 1,585 24.8% +6.2 1.5% 19 Late aircraft
RNO Reno, NV 1,576 18.5% -2.5 3.9% 12 Late aircraft
SDF Louisville, KY 1,575 21.7% +6.0 1.7% 15 Late aircraft
CHS Charleston, SC 1,568 22.4% +4.4 3.1% 14 Late aircraft
MEM Memphis, TN 1,456 22.9% +2.7 1.9% 17 Late aircraft
PSP Palm Springs, CA 1,444 20.4% +1.4 0.4% 13 Late aircraft
BUF Buffalo, NY 1,392 26.9% +5.0 2.6% 21 Late aircraft
ORF Norfolk, VA 1,289 23.5% +7.9 4.1% 19 Late aircraft
LGB Long Beach, CA 1,275 15.5% -0.7 0.6% 8 Late aircraft
SAV Savannah, GA 1,266 24.8% +8.0 2.8% 19 Late aircraft
GRR Grand Rapids, MI 1,236 24.1% +4.6 1.5% 17 Late aircraft
ELP El Paso, TX 1,235 16.8% -0.8 0.5% 11 Late aircraft
TUL Tulsa, OK 1,233 21.2% +2.8 3.1% 16 Airline
KOA Kona, HI 1,227 12.2% -5.2 0.0% 7 Airline
LIH Lihue, HI 1,178 15.0% -1.4 0.3% 9 Airline
GEG Spokane, WA 1,148 23.5% +4.7 0.3% 13 Airline
PVD Providence, RI 1,136 24.1% +7.5 3.3% 19 Late aircraft
BHM Birmingham, AL 1,115 24.2% +8.1 2.2% 17 Late aircraft
RIC Richmond, VA 1,102 21.1% +1.5 2.5% 14 Airline
ANC Anchorage, AK 1,078 15.9% -12.1 1.3% 9 Late aircraft
GSP Greer, SC 1,058 26.0% +11.8 2.2% 18 Late aircraft
83 airports with 1,000+ flights this month, busiest first. Click a header to sort.

Airlines — arrivals 15+ min late

AirlineFlightsLateCanc.
Southwest100,19916.5%0.6%
Hawaiian6,01317.3%0.3%
Spirit16,23218.7%1.1%
United57,62818.7%0.3%
Envoy19,99519.1%1.7%
Delta71,33320.0%0.2%
American69,87620.5%1.3%
Alaska16,31521.1%2.2%
Republic25,48321.5%3.5%
SkyWest59,80623.7%1.8%
Allegiant9,37125.0%0.9%
Frontier15,44025.2%1.3%
JetBlue17,68528.5%2.6%
PSA19,50836.2%10.2%
Regional airlines (SkyWest, Envoy, Republic, PSA…) fly under the big brands' names.

Worst days this month

DateAirportLateCanc.
02-06DCA 77%13%
02-13LAS 77%12%
02-17LGA 75%14%
02-13SFO 78%7%
02-13DCA 77%8%
02-06SFO 75%4%
02-12DCA 70%19%
02-16FLL 70%12%
02-16TPA 71%9%
02-16BOS 65%21%
Ranked by share of flights late or cancelled; airports with 150+ flights that day.

FAA programs and delays, last 7 days

AirportWhatStarted (UTC)HoursPeak avgReason
LGAGround stop 11-07 19:30 0.8+ — wind
BOSGround stop 11-07 19:15 0.5 — runway construction
MCODeparture delays 11-07 18:15 2.0 31 min RWY:Maintenance
MIADeparture delays 11-07 18:00 0.5 16 min RWY:Construction
BOSDeparture delays 11-07 14:00 4.2 61 min RWY:Construction
BOSGround delay program 11-07 13:00 7.3+ 148 min runway construction
SEAGround delay program 11-07 01:30 4.0 51 min other
LGAGround stop 11-07 00:45 1.0 — airport volume
PHLDeparture delays 11-07 00:30 1.7 31 min TM Initiatives:SWAP:WX
SEADeparture delays 11-07 00:30 1.2 16 min RWY:Construction
JFKDeparture delays 11-07 00:15 1.8 16 min TM Initiatives:SWAP:WX
MCODeparture delays 11-07 00:15 0.3 16 min RWY:CLSD EQUIP OUTAGE
LASDeparture delays 11-06 23:45 2.3 16 min VOL:Volume
SANDeparture delays 11-06 23:15 1.5 31 min VOL:Compacted Demand
SEADeparture delays 11-06 21:30 0.5 16 min RWY:Construction
HPNGround stop 11-06 21:00 1.0 — thunderstorms
SANDeparture delays 11-06 20:30 2.2 16 min VOL:Compacted Demand
OPFDeparture delays 11-06 20:15 0.2 16 min VOL:Compacted Demand
EWRGround stop 11-06 19:00 2.0 — thunderstorms
BFIGround stop 11-06 19:00 0.7 — other
SANDeparture delays 11-06 19:00 0.2 16 min VOL:Volume
BFIGround delay program 11-06 18:30 6.5 258 min other
PHXDeparture delays 11-06 17:30 0.5 16 min VOL:Multi-taxi
EWRGround delay program 11-06 17:15 11.0 156 min thunderstorms
BOSGround stop 11-06 16:45 2.0 — thunderstorms
BOSDeparture delays 11-06 16:45 2.5 46 min WX:Thunderstorms
OPFDeparture delays 11-06 16:45 0.2 16 min TM Initiatives:MINIT:VOL
LGAGround stop 11-06 16:30 5.5 — thunderstorms
JFKGround stop 11-06 16:15 3.2 — thunderstorms
EWRGround stop 11-06 16:00 1.2 — thunderstorms
DCADeparture delays 11-06 16:00 5.5 136 min TM Initiatives:SWAP:WX
MIADeparture delays 11-06 16:00 0.5 31 min TM INITIATIVES:OTHER:CFR
ORDDeparture delays 11-06 15:45 0.5 16 min VOL:Multi-taxi
BOSGround delay program 11-06 15:30 8.5 144 min thunderstorms
SANGround delay program 11-06 15:00 12.7 26 min airport volume
SANDeparture delays 11-06 15:00 3.0 16 min VOL:Volume
DALDeparture delays 11-06 14:15 0.2 16 min VOL:Volume
BWIDeparture delays 11-06 14:00 6.5 136 min TM Initiatives:SWAP:WX
ORDDeparture delays 11-06 14:00 0.2 31 min VOL:Multi-taxi
PHLDeparture delays 11-06 14:00 7.7 241 min TM Initiatives:SWAP:WX
EWRGround stop 11-06 13:45 1.5 — thunderstorms
OPFDeparture delays 11-06 13:45 0.2 16 min VOL:Compacted Demand
LGAGround delay program 11-06 13:15 12.5 174 min thunderstorms
TEBDeparture delays 11-06 13:00 12.2 361 min TM Initiatives:SWAP:WX
DCADeparture delays 11-06 12:45 0.8 61 min WX:Thunderstorms
EWRDeparture delays 11-06 12:45 10.0 211 min TM Initiatives:SWAP:WX
JFKDeparture delays 11-06 12:30 10.0 136 min TM Initiatives:SWAP:WX
LGAGround stop 11-06 12:00 1.2 — thunderstorms
LGADeparture delays 11-06 11:45 12.5 166 min TM Initiatives:SWAP:WX
TEBDeparture delays 11-06 11:45 0.7 31 min TM Initiatives:SWAP:WX
JFKGround stop 11-06 11:15 4.8 — thunderstorms
BOSGround stop 11-05 23:30 0.8 — airspace volume
BFIGround delay program 11-05 22:15 6.8 161 min other
BFIGround stop 11-05 21:30 0.8 — other
SANDeparture delays 11-05 21:15 0.8 16 min VOL:Compacted Demand
BFIDeparture delays 11-05 21:00 3.0 16 min OTHER: TEMP TOWER OPS
SANDeparture delays 11-05 20:00 0.2 16 min VOL:Compacted Demand
HOUGround stop 11-05 19:45 0.2 — aircraft emergency
BFIGround stop 11-05 19:30 0.5 — other
DALDeparture delays 11-05 19:15 0.2 16 min VOL:Volume
OPFDeparture delays 11-05 18:45 0.5 16 min VOL:Compacted Demand
SEADeparture delays 11-05 17:15 0.2 16 min RWY:Construction
BFIGround stop 11-05 16:30 1.0 — airport volume
EWRDeparture delays 11-05 14:30 1.5 31 min TM Initiatives:MINIT:VOL
SANGround delay program 11-05 14:15 13.5 38 min airport volume
LGADeparture delays 11-05 14:15 1.8 16 min TM Initiatives:MINIT:WX
PHLDeparture delays 11-05 14:15 1.8 16 min TM Initiatives:MIT:VOL
TEBDeparture delays 11-05 14:15 7.5 76 min TM Initiatives:Metering:VOL
MIADeparture delays 11-05 02:15 0.2 16 min VOL:Multi-taxi
SANDeparture delays 11-05 01:45 3.0 31 min VOL:Compacted Demand
ATLGround stop 11-04 22:45 0.7 — thunderstorms
DALDeparture delays 11-04 22:45 2.5 16 min VOL:Volume
LGADeparture delays 11-04 22:15 0.7 31 min TM Initiatives:MINIT:VOL
SANDeparture delays 11-04 21:45 2.3 16 min VOL:Volume
OPFDeparture delays 11-04 19:30 0.2 16 min WX:Thunderstorms
MIADeparture delays 11-04 18:45 0.3 15 min WX:Thunderstorms
MIADeparture delays 11-04 16:15 2.2 46 min WX:Thunderstorms
ATLGround stop 11-04 16:00 2.0 — thunderstorms
ATLDeparture delays 11-04 16:00 2.5 46 min WX:Thunderstorms
SANGround delay program 11-04 14:45 6.5 37 min airport volume
FLLDeparture delays 11-04 02:15 10.0 46 min TM Initiatives:MIT:WX
MIADeparture delays 11-04 01:30 10.7 31 min TM Initiatives:MIT:WX
FLLDeparture delays 11-04 00:45 1.0 46 min TM Initiatives:MIT:WX
TEBDeparture delays 11-03 21:30 2.8 31 min STAFF:Staffing
SFODeparture delays 11-03 19:30 2.8 16 min WX:Wind
IAHDeparture delays 11-03 18:45 8.8 76 min WX:Thunderstorms
HOUGround stop 11-03 18:30 1.0 — thunderstorms
IAHGround stop 11-03 18:30 1.0 — thunderstorms
SANDeparture delays 11-03 18:00 0.2 16 min VOL:Compacted Demand
EWRDeparture delays 11-03 17:30 0.2 31 min STAFF:Staffing
PHXDeparture delays 11-03 17:30 0.5 16 min VOL:Multi-taxi
MIADeparture delays 11-03 17:00 2.2 16 min RWY:Construction
SFOGround stop 11-03 16:45 0.7 — wind
IAHDeparture delays 11-03 16:45 1.0 31 min WX:Thunderstorms
MCODeparture delays 11-03 16:45 0.5 16 min TM Initiatives:MIT:WX
TEBDeparture delays 11-03 15:30 2.5 46 min STAFF:Staffing
EWRDeparture delays 11-03 15:00 2.2 16 min STAFF:Staffing
SFOGround delay program 11-03 14:15 14.5 114 min wind
MIADeparture delays 11-03 14:00 0.7 16 min WX:Thunderstorms
DALDeparture delays 11-03 03:30 5.0 46 min WX:Thunderstorms
SANDeparture delays 11-03 03:30 1.5 16 min VOL:Compacted Demand
FLLGround stop 11-03 02:30 1.2 — thunderstorms
MIAGround delay program 11-03 00:00 4.0 146 min thunderstorms
MIADeparture delays 11-03 00:00 3.2 91 min TM Initiatives:MIT:WX
SANDeparture delays 11-02 22:30 4.8 16 min VOL:Compacted Demand
LGAGround stop 11-02 21:30 0.7 — airspace volume
ORDDeparture delays 11-02 21:15 1.8 15 min WX:Low Ceilings
FLLGround stop 11-02 21:00 3.2 — thunderstorms
ASEArrival delays 11-02 21:00 3.2 16 min ASE / WX:Low Ceilings
DJTDeparture delays 11-02 21:00 3.2 61 min WX:Thunderstorms
MIAGround stop 11-02 20:30 3.5 — thunderstorms
PHXDeparture delays 11-02 19:00 0.2 16 min VOL:Multi-taxi
DJTGround stop 11-02 18:45 1.8 — thunderstorms
FLLGround delay program 11-02 18:45 9.8 133 min thunderstorms
MIAGround stop 11-02 18:30 1.5 — thunderstorms
ORDDeparture delays 11-02 18:30 0.2 16 min WX:Low Ceilings
FLLGround stop 11-02 18:00 0.8 — thunderstorms
FMYDeparture delays 11-02 18:00 6.3 61 min WX:Thunderstorms
PHXDeparture delays 11-02 17:30 0.5 16 min VOL:Multi-taxi
SEADeparture delays 11-02 16:15 3.5 31 min WX:Fog
APFDeparture delays 11-02 16:00 8.2 121 min WX:Thunderstorms
MIAGround stop 11-02 14:15 2.5 — thunderstorms
FLLGround stop 11-02 14:15 2.8 — thunderstorms
DJTGround stop 11-02 14:15 2.8 — thunderstorms
SANGround delay program 11-02 13:45 12.0 29 min airport volume
TEBDeparture delays 11-02 13:45 4.2 46 min OTHER: INDIVIDUAL RELEASE
OPFDeparture delays 11-02 13:30 9.7 16 min TM Initiatives:MINIT:WX
RSWDeparture delays 11-02 13:15 11.0 91 min WX:Thunderstorms
FLLDeparture delays 11-02 13:00 14.3 166 min TM Initiatives:MIT:WX
MIADeparture delays 11-02 13:00 6.8 106 min TM Initiatives:MIT:WX
SFOGround delay program 11-02 03:00 1.2 62 min other
SFOGround stop 11-02 02:30 0.5 — STAFFING
MCODeparture delays 11-02 02:15 3.0 31 min WX:Thunderstorms
MCODeparture delays 11-02 00:30 1.5 31 min TM Initiatives:MIT:WX
LASDeparture delays 11-01 23:30 0.5 16 min WX:Thunderstorms
DCADeparture delays 11-01 23:15 0.5 16 min TM Initiatives:ESP:VOL
LASGround delay program 11-01 23:00 2.7 49 min wind
DJTGround stop 11-01 21:45 2.3 — thunderstorms
LASGround stop 11-01 21:30 1.5 — wind
YEGGround stop 11-01 21:30 7.5 — fog
SANDeparture delays 11-01 21:15 1.8 16 min VOL:Compacted Demand
DJTDeparture delays 11-01 20:30 5.5 76 min WX:Thunderstorms
MCODeparture delays 11-01 20:30 3.7 31 min TM Initiatives:MIT:WX
MIADeparture delays 11-01 19:45 9.5 76 min TM Initiatives:MIT:WX
PHXDeparture delays 11-01 19:30 3.5 31 min RWY:Rwy Change - Operational Necessity
PHXGround stop 11-01 19:15 1.3 — wind
RSWDeparture delays 11-01 18:15 6.0 16 min WX:Thunderstorms
ORDDeparture delays 11-01 17:30 1.0 16 min VOL:Volume
PHXDeparture delays 11-01 17:30 1.2 16 min WX:Low Ceilings
YEGGround stop 11-01 17:15 2.0 — fog
PHXGround stop 11-01 17:00 0.7 — low ceilings
LASDeparture delays 11-01 17:00 6.2 16 min WX:Thunderstorms
FLLGround delay program 11-01 16:45 6.5 56 min thunderstorms
LASDeparture delays 11-01 16:00 0.2 16 min WX:Wind
FLLGround stop 11-01 15:30 1.2 — THUNDERSTORMS
PHLDeparture delays 11-01 15:00 0.5 31 min TM Initiatives:MIT:STAFFING
FLLDeparture delays 11-01 13:45 15.5 151 min TM Initiatives:MIT:WX
MIADeparture delays 11-01 13:45 4.5 31 min TM Initiatives:MIT:WX
DFWDeparture delays 11-01 13:30 7.3 61 min WX:Low Visibility
DFWGround stop 11-01 13:00 1.0 — LOW
LASDeparture delays 10-31 21:15 0.2 16 min VOL:Compacted Demand

Most disrupted, last 30 days (FAA)

AirportGSGDPDelayHours
SAN41827232
LAS10926115
LGA9223106
BOS7713100
MIA313897
TEB312591
SFO510783
FLL521073
EWR741069
YUL011060
PHX442548
AUS37043
DCA51739
PHL111033
SEA212331
Recording since 2026-10-14. The FAA keeps no public history, so this is only what we have polled (every 15 minutes).
Sources. Delay rates: US DOT Bureau of Transportation Statistics, Reporting Carrier On-Time Performance (public domain). It covers domestic flights on airlines with at least 0.5% of US domestic passenger revenue, about 600,000 flights a month; smaller carriers and international flights are not in it. Live status: FAA Air Traffic Control System Command Center, NAS Status (public domain). Airport locations: OurAirports (public domain).
Definitions. Late means 15+ minutes after schedule, out of flights that operated. Causes are reported by airlines for arrivals 15+ minutes late. "Late aircraft" is the knock-on from an earlier delay to the same plane, so it says nothing about where the trouble started. "Air traffic" (the NAS category) covers airport capacity, traffic volume and non-extreme weather. "Usual" is the median of the same month in up to five earlier years, with 2020 left out; it appears once two earlier years exist.