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 20:00 UTC

MCO · Departure delays
31 minutes to 45 minutes, increasing · RWY:Maintenance
since 11-07 18:15 UTC (first seen)
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 2026

19.8%
of 502,396 arrivals ran 15+ min late · usual for February: 18.9% · 2.3% 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
Airline 38%
Late aircraft 37%
Air traffic 19%
Weather 6%
Security 0%

Airports, February 2026 (arrivals)

AirportCityFlightsLate 15+ vs usual CancelledAvg minMain cause
ORD Chicago, IL 25,535 22.2% +3.7 1.2% 18 Late aircraft
DEN Denver, CO 23,037 17.5% -2.7 1.0% 15 Air traffic
ATL Atlanta, GA 23,020 14.8% +2.1 1.7% 12 Airline
DFW Dallas/Fort Worth, TX 22,011 16.7% -3.7 1.4% 15 Airline
PHX Phoenix, AZ 15,649 16.5% +0.3 0.8% 12 Airline
LAX Los Angeles, CA 13,677 19.2% +0.6 1.5% 14 Airline
MCO Orlando, FL 13,336 22.3% +1.4 2.5% 17 Late aircraft
CLT Charlotte, NC 13,186 17.1% +2.6 3.8% 17 Airline
LAS Las Vegas, NV 12,883 17.4% -2.8 0.9% 11 Late aircraft
SEA Seattle, WA 10,997 15.0% -3.1 1.0% 10 Airline
DCA Washington, DC 10,996 33.3% +17.6 4.4% 26 Late aircraft
SFO San Francisco, CA 10,320 25.5% +2.6 1.3% 19 Air traffic
LGA New York, NY 10,307 23.1% +2.6 8.3% 16 Late aircraft
BOS Boston, MA 10,233 24.9% +3.9 8.0% 19 Late aircraft
MIA Miami, FL 9,304 19.9% +1.3 2.0% 16 Late aircraft
EWR Newark, NJ 9,288 19.3% -0.5 8.1% 14 Late aircraft
SLC Salt Lake City, UT 9,172 14.7% +1.6 1.0% 12 Airline
DTW Detroit, MI 9,117 21.3% +5.4 2.3% 19 Airline
IAH Houston, TX 8,973 11.6% -6.4 1.0% 9 Airline
FLL Fort Lauderdale, FL 8,256 26.8% +5.0 4.2% 19 Late aircraft
MSP Minneapolis, MN 7,920 17.7% +2.9 1.2% 15 Airline
BNA Nashville, TN 7,547 18.0% +2.1 1.6% 10 Late aircraft
JFK New York, NY 7,454 24.0% +3.7 8.7% 22 Late aircraft
SAN San Diego, CA 7,008 20.4% +0.4 0.9% 11 Late aircraft
PHL Philadelphia, PA 6,687 21.5% +4.3 6.2% 18 Late aircraft
BWI Baltimore, MD 6,551 18.2% +5.0 3.7% 10 Late aircraft
AUS Austin, TX 6,473 16.6% -1.6 1.1% 11 Airline
TPA Tampa, FL 6,177 19.9% +1.3 2.3% 13 Late aircraft
DAL Dallas, TX 5,162 15.9% +2.1 1.2% 9 Late aircraft
MDW Chicago, IL 4,537 17.9% +5.5 1.1% 10 Late aircraft
STL St. Louis, MO 4,486 16.6% +1.1 1.2% 10 Late aircraft
HNL Honolulu, HI 4,472 22.1% +5.6 1.2% 13 Airline
PDX Portland, OR 4,177 14.9% -2.3 0.7% 10 Airline
MSY New Orleans, LA 4,112 17.8% -0.3 1.5% 13 Airline
IAD Washington, DC 3,983 15.0% -0.1 1.4% 12 Late aircraft
RDU Raleigh/Durham, NC 3,955 22.0% +4.7 3.0% 15 Late aircraft
SMF Sacramento, CA 3,934 16.5% +0.2 0.3% 10 Late aircraft
HOU Houston, TX 3,830 14.5% +0.1 0.7% 8 Late aircraft
RSW Fort Myers, FL 3,555 22.8% +1.6 2.8% 15 Late aircraft
MCI Kansas City, MO 3,506 18.8% +0.0 1.4% 12 Late aircraft
IND Indianapolis, IN 3,458 21.4% +5.5 2.5% 14 Late aircraft
SNA Santa Ana, CA 3,342 15.0% -1.7 0.6% 9 Airline
CMH Columbus, OH 3,231 21.7% +5.3 2.9% 14 Late aircraft
SJC San Jose, CA 3,089 15.7% +0.5 0.4% 9 Late aircraft
PBI West Palm Beach/Palm Beach, FL 2,970 27.2% +1.8 4.7% 18 Late aircraft
PIT Pittsburgh, PA 2,943 21.0% +6.6 2.5% 14 Late aircraft
SJU San Juan, PR 2,841 29.4% +6.7 3.2% 23 Late aircraft
CLE Cleveland, OH 2,769 22.4% +4.3 2.0% 14 Airline
SAT San Antonio, TX 2,671 17.4% -1.4 1.1% 11 Late aircraft
OAK Oakland, CA 2,356 15.3% +1.6 0.4% 9 Late aircraft
CVG Cincinnati, OH 2,271 22.3% +5.8 1.6% 16 Late aircraft
BUR Burbank, CA 2,135 16.3% +0.5 2.1% 10 Late aircraft
MKE Milwaukee, WI 2,036 24.2% +4.7 1.3% 17 Airline
JAX Jacksonville, FL 2,025 20.6% +2.3 2.4% 12 Late aircraft
OGG Kahului, HI 1,965 19.8% +6.6 0.6% 10 Airline
OMA Omaha, NE 1,803 19.6% -0.1 0.4% 12 Airline
BOI Boise, ID 1,783 16.2% +0.4 0.1% 11 Late aircraft
ONT Ontario, CA 1,733 16.8% +0.3 0.2% 10 Late aircraft
BDL Hartford, CT 1,688 27.2% +7.7 6.7% 18 Late aircraft
SRQ Sarasota/Bradenton, FL 1,684 18.5% -3.2 2.4% 13 Late aircraft
OKC Oklahoma City, OK 1,681 17.9% -2.7 0.7% 13 Airline
ABQ Albuquerque, NM 1,680 15.9% -1.5 0.3% 9 Late aircraft
CHS Charleston, SC 1,679 21.5% +3.5 2.4% 15 Late aircraft
TUS Tucson, AZ 1,646 18.9% +0.2 0.1% 13 Airline
RNO Reno, NV 1,621 18.1% -0.3 1.1% 13 Late aircraft
MEM Memphis, TN 1,609 22.1% +1.9 1.7% 14 Late aircraft
SDF Louisville, KY 1,599 21.7% +6.0 2.5% 14 Late aircraft
PSP Palm Springs, CA 1,493 19.4% +0.3 0.5% 12 Late aircraft
RIC Richmond, VA 1,458 21.1% +1.5 3.6% 14 Late aircraft
BUF Buffalo, NY 1,392 29.8% +7.8 3.5% 27 Late aircraft
GRR Grand Rapids, MI 1,378 24.9% +5.4 1.1% 16 Airline
ORF Norfolk, VA 1,330 21.4% +5.9 3.1% 15 Late aircraft
GEG Spokane, WA 1,300 16.2% -2.5 0.3% 11 Late aircraft
KOA Kona, HI 1,276 20.4% +8.2 0.3% 10 Airline
TUL Tulsa, OK 1,265 19.3% +0.9 0.9% 13 Airline
ANC Anchorage, AK 1,221 21.1% -6.9 1.3% 12 Late aircraft
SAV Savannah, GA 1,220 19.9% +3.1 2.8% 14 Late aircraft
LIH Lihue, HI 1,161 21.1% +6.1 1.7% 10 Airline
ELP El Paso, TX 1,160 16.8% -0.2 0.7% 12 Airline
BHM Birmingham, AL 1,149 20.1% +3.9 1.0% 12 Late aircraft
PVD Providence, RI 1,136 28.3% +11.7 8.3% 18 Airline
LGB Long Beach, CA 1,129 17.7% +2.3 0.2% 9 Late aircraft
DSM Des Moines, IA 1,095 22.3% +3.9 1.0% 15 Late aircraft
GSP Greer, SC 1,056 23.3% +9.0 2.4% 15 Late aircraft
ASE Aspen, CO 1,012 37.4% -0.4 7.5% 38 Air traffic
XNA Fayetteville, AR 1,007 18.3% +1.5 1.4% 15 Airline
86 airports with 1,000+ flights this month, busiest first. Click a header to sort.

Airlines — arrivals 15+ min late

AirlineFlightsLateCanc.
United59,80615.8%1.6%
Envoy22,72816.6%0.8%
Delta74,20016.7%2.1%
Alaska24,01317.1%1.2%
Southwest100,78318.3%1.0%
Republic27,45820.1%6.9%
American72,78621.1%2.1%
Frontier15,05621.6%1.4%
SkyWest62,07321.8%1.2%
Allegiant9,08722.0%0.7%
PSA17,66427.0%4.8%
Spirit11,51231.7%8.0%
JetBlue17,87132.3%7.7%
Regional airlines (SkyWest, Envoy, Republic, PSA…) fly under the big brands' names.

Worst days this month

DateAirportLateCanc.
02-23BOS 100%98%
02-23EWR 100%100%
02-23JFK 100%98%
02-23LGA —100%
02-24JFK 80%41%
02-22JFK 36%77%
02-01CLT 53%64%
02-22LGA 35%68%
02-23PHL 29%70%
02-17DEN 75%7%
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 0.5+ — wind
BOSGround stop 11-07 19:15 0.5 — runway construction
MCODeparture delays 11-07 18:15 1.8+ 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 7.0+ 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.