DL20Delta Air Lines · SEA → LHR
live · 26m ago
Route confirmed Delta Air Lines

DL20 SeattleSEA · 16:50 LondonLHR · 10:40

DL20 by Delta Air Lines flies from Seattle (SEA) to London (LHR) for the Fri, Nov 13 departure.

Same number through SEA → BOS → LHR

Right nowOn time · gate A3 · as of 04:20
16:50

departs SEA · on schedule

Typical arrival+30 minmedian over 5 operations

Where the minutes go

last 5 operations · gate push → arrival
0+30+60+90 min
11-13
+30 arrival
11-12
+30 arrival
11-11
−18 arrival
11-10
−21 arrival
11-09
+79 arrival

The bar is how late it left the gate; the ring is where it actually arrived. Board clocks, not estimates.

The last 30 days

arrival outcome per operation

median arrival +30 min · 0 cancelled · 5 operations tracked

The route today

live boards
SEASeattleHigh riskSEA delay board →
LHRLondonOn-time likelyLHR delay board →
SEA→LHRevery carrier, schedules and on-time historyRoute intelligence →

Weather lens

Delay & cancellation outlook for this flight

Measured, 90-day sample
29%Chance of 15+ min delay
2.7%Chance of cancellation
-1 minTypical airport delay in this weather

Conditions at SEA and LHR are near their clear-air norm right now, so this reflects the route's recent baseline rather than a weather penalty. These figures come from both airports' records under conditions like today's, over the last 90 days.

Pro Flight Search tracking, 90 days · the weather × delay correlation study → · live weather risk by airport →

Tomorrow at Seattle

Forecast

Sat 14 Nov, local date

High14°Clikely 13°C to 16°C
Low10°Clikely 8°C to 11°C
  • 92% chance of rain

Forecast: GateWeather · incl. data from ECMWF (CC BY 4.0, modified) · Expected values for tomorrow from a forecast model, kept apart from today's measured figures.

Tomorrow at London

Forecast

Sat 14 Nov, local date

High9°Clikely 8°C to 10°C
Low−2°Clikely −3°C to 0°C

Forecast: GateWeather · incl. data from ECMWF (CC BY 4.0, modified) · Expected values for tomorrow from a forecast model, kept apart from today's measured figures.

When it flies

scheduled departures
061422
M
T
W
T
F
S
S

Each mark is a scheduled departure at its origin-local time. Today is highlighted.

Other Seattle to London flights today

same route · Delta Air Lines
DL9979departs 06:30

If DL20 is cancelled, this is the other Delta Air Lines nonstop flight from Seattle to London on the same day, with scheduled departure times in SEA local time. Most flights that show a delay still operate. Rebooking usually helps only when that delay is very large. Every airline on this route →

How DL20 actually runs

Pro Flight Search has tracked every published board update for DL20 across the SEA and LHR boards: schedule changes, gate pushes and actual clocks. Usually lands ~30 min late. Based on 5 confirmed landings · 2/5 within 15 min of schedule.

The verdict above is that record speaking, so it reflects how DL20 operates rather than what the timetable promises. Numbers refresh as new flights operate.

Technical record

How this operation is measured

board clocks

Board log

scheduled → actual, per operation
11-13SEA 16:50LHR 10:40 11:10 (+30)
11-12SEA 16:50LHR 10:40 11:10 (+30)
11-11SEA 16:50LHR 10:40 10:22 (−18)
11-10SEA 16:50LHR 10:40 10:19 (−21)
11-09SEA 16:50LHR 10:40 11:59 (+79)

Board clocks recorded as SEA and LHR published them.

Planning around DL20? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure

Cite this data

Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.

Suggested citation

Pro Flight Search: DL20 Seattle to London on-time performance, measured from the SEA and LHR airport boards.

Canonical URL
https://proflightsearch.com/flight/DL20
How we measure this →