Tsunamis in 1941

February 9, 1941 Tsunami: Northern California, United States

February 9, 1941 · An event that only caused a seiche

A tsunami of meteorological origin began at Northern California, United States on February 9, 1941 at 09:44:04 UTC. Its effects were recorded at 3 places.

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

Tsunami warnings in force

The tsunami

Date
February 9, 1941, 09:44:04 UTC
Source
Northern California, United States
Cause
Meteorological
Earthquake
Magnitude 6.6
Runups recorded
3
Waters
Ocean
How certain
An event that only caused a seiche
Source location
40.500° N, 125.250° W

The toll

Damage
Limited (under about $1 million) with the earthquake or eruption that caused it

Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.

What the record says

NCEI’s account, from the sources it cites.

There was an earthquake with epicenter at point 40.9" N., 125.4" W.; M=6.6. There was an overall intensification of seiches in the harbor 14 hours later in San Francisco and San Diego; 36 hours later, the same occurred at Port Hueneme. There were no changes at La Jolla. The conclusions are based on tide gauge records (Joy, 1968). Note: Listed as questionable tsunami. (reference #415)

Reference #237 lists a validity 0 (defined as "Date is proven to be in error; source of water disturbance is known to be from a meteorological or an astronomic tide source; reported tsunami effects shown to be in error in later documents which are based on primary references."). The long time delay between the shock and the seiche, the absence of reports of waves nearer the source and the presence of a storm in the area are convincing evidence for a meteorological cause. (reference #237)

Every runup

Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.

WhereCountryKm from sourceWater height, mInland, mMeasured byFirst wave, UTCDeaths
San Francisco, CA, CAUnited States384Other
Port Hueneme, CA, CAUnited States886Other
San Diego, CA, CAUnited States1,125Other

More

Every tsunami in 1941The 1900sTsunamis of United StatesThe earthquakeThis 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 1745.