February 17, 1855 Tsunami: Azores, Portugal
A tsunami of unknown cause began at Azores, Portugal on February 17, 1855. The water rose as high as 10 meters. Its effects were recorded at 1 place.
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
The tsunami
- Date
- February 17, 1855
- Source
- Azores, Portugal
- Cause
- Unknown
- Maximum water height
- 10 m (32.8 ft)
- Runups recorded
- 1
- Tsunami magnitude (Iida)
- 1.6
- Waters
- Ocean
- How certain
- Questionable tsunami
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.
1855, February 17. Azores. Tsunami at Ilha Terceira. The sea invaded the coast on the south and east of the island rising to a height of about 10 meters.(reference #41)
1855, February 17. Very doubtful tsunami, Meteorological cause. On 17 February 1855 the sea invaded the southern and eastern coasts of Terceira Island up to a height of 10 m (Agostinho 1935). This description, although very summarized, is similar to others regarding events reported by this author on Terceira Island during severe storms. Since there is no known report of any occurrence, local or distant, that might have been the source to this flood, the most probable cause is a meteorological phenomenon. (reference #13057)
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 |
|---|---|---|---|---|---|---|---|
| Ilha Terceira, Azores | Azores | 10 | Eyewitness observation of water height |
More
Every tsunami in 1855The 1800sTsunamis of PortugalThis 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 843.