July 17, 1969 Tsunami: Southwest Iberian, Atlantic Ocean
A tsunami of unknown cause began at Southwest Iberian, Atlantic Ocean on July 17, 1969 at 05:00 UTC. The water rose as high as 0.06 meters. Its effects were recorded at 5 places in at least 3 countries.
Where the waves reached
The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.
- Under 1 m
- 1 to 3 m
- 3 to 10 m
- 10 to 30 m
- 30 m and more
- Height not recorded
Travel times
How long the first wave took to reach each part of the ocean, one line for each hour up to 24, estimated from the source and the depth of the sea.
The travel times are computed in your browser, which needs JavaScript.
- 1 to 4 hours
- 5 to 6 hours
- 7 to 14 hours
- 15 hours and more
Computed in your browser the way NOAA’s own travel time maps are: the wave travels at the square root of gravity times the depth, over NOAA’s ETOPO1 depths averaged to a 10 arc-minute grid. Checked against NOAA NCEI’s maps for 21 tsunamis over the first 24 hours, these lines fall within 10 minutes of NCEI’s at half the points compared and within 52 minutes at 9 in 10. They give when the first wave could arrive, not how high it is; bays, harbors and island chains finer than the grid can see it later. Not for use in a warning: see tsunami.gov.
The tsunami
- Date
- July 17, 1969, 05:00 UTC
- Source
- Southwest Iberian, Atlantic Ocean
- Cause
- Unknown
- Maximum water height
- 0.06 m (0.2 ft)
- Runups recorded
- 5
- Waters
- Ocean
- How certain
- Definite tsunami
- Source location
- 28.450° N, 16.260° W
The toll
The record gives no deaths, injuries or damage for this tsunami.
What the record says
NCEI’s account, from the sources it cites.
1969 July 17, 28.45 N 16.26 W, Event reliability 4. (reference #11164)
1969 July 17, 05:00:00 UTC, Event reliability 4. (reference #4649)
There are no seismic events with tsunamigenic potential known at this date in the North Atlantic or other nearby areas. Also, no anomalous meteorological conditions have been reported, thus the source of the 17 July 1969 tsunami remains unknown. (reference #13057)
1969 July 17, 37 N 12 W (reference #12955)
Every runup
Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.
| Where | Country | Km from source | Water height, m | Inland, m | Measured by | First wave, UTC | Deaths |
|---|---|---|---|---|---|---|---|
| Santa Cruz, Tenerife, Canary Is | Spain | 4 | 0.19 | Tide gauge (half the maximum wave height) | day 17, 04:15 | ||
| Arrecife, Lanzarote Island | Spain | 273 | 0.04 | Tide gauge (half the maximum wave height) | |||
| Lagos | Portugal | 1,193 | 0.06 | Tide gauge (half the maximum wave height) | |||
| Cascais | Portugal | 1,301 | Tide gauge (half the maximum wave height) | ||||
| Angra do Heroismo, Terceira | Azores | 1,521 | Tide gauge (half the maximum wave height) |
More
Every tsunami in 1969The 1900sTsunamis of Atlantic OceanThis day in weather historyAlerts in force
Sources
Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI tsunami event 5784.