National Tsunami Warning Center, NOAA/NWS

TSUNAMI of 25 September 2003

A great earthquake with a moment magnitude of 8.0 occurred at 1950 UTC 25 September 2003 and was located near Hokkaido, Japan Region (41.89N 143.77E, 10km depth - USGS location).

The earthquake produced a tsunami that was recorded at several tide gages (operated by NOAA/National Ocean Survey, the Pacific Tsunami Warning Center, the University of Hawaii, and the Japanese Meteorological Agency). If available, click on the site name to see a graph of the tsunami. Wave heights are maximum peak-to-trough height in cm. Arrival time is the actual tsunami arrival time in UTC on gages where it could be determined. The ETA is the estimated time of arrival computed at the National Tsunami Warning Center (NTWC) based on the origin time and location. The Sample Interval column shows the time between samples. (NOTE: for the 0.25 minute sample, the interval may vary). Click on the Data File column to get the raw data for NOAA/NOS Alaska tide gages which have a 0.25minute real-time output to the NTWC. Data can be saved using text mode with your browser. Time in these data files is the modified Julian time in seconds times 100. Water level values are given in cm. The first sample in the file is the first sample of the day. For additional information about this tsunami see PMEL's Tsunami Research Web Page .

Tide gage site Wave height (cm p-t) Arrival time (UTC) ETA (UTC) Initial motion Sample Interval (min) Data File
Hanasaki, Japan 213 2026    9/25 2023 9/25 rise 6  
Ofunato, Japan 35 2047    9/25 2054 9/25 rise 6  
Midway Island 12 0050    9/26 0039 9/26 ? 6  
French Frigate Shoal, Hawaii 4   ? 0211 9/26 ? 6  
Kalaupapa, Hawaii ~10 0315    9/26 ? rise .25  
Kawaihae, Hawaii 10 0340    9/26 ? rise 6  
Honolulu, Hawaii 6 0328    9/26 0321 9/26 rise 6  
Kahului, Hawaii 40 0330    9/26 0333 9/26 rise 6  
Hilo, Hawaii 13 0345    9/26 0342 9/26 rise 6  
Honokahau, Hawaii 8 0342    9/26 ? rise .25  
Adak, Alaska 8 0010    9/26 0007 9/26 rise .25 Data starting on 9/26 0000Z
Dutch Harbor, Alaska 7 0133    9/26 0117 9/26 rise .25 Data starting on 9/26 0000Z
Port Orford, Oregon 7 ? ? ? 6 Data starting on 9/26 0000Z
Crescent City, California 35 0530    9/26 0522 9/26 ? 6 Data starting on 9/26 0000Z
Humboldt Bay, California 8 ? 0522 9/26 ? 6 Data starting on 9/26 0000Z
Point Arena, California 4 0520    9/26 0523 9/26 ? 6 Data starting on 9/26 0000Z
Point Reyes, California 6 ? 0534 9/26 ? 6 Data starting on 9/26 0000Z
Pt. San Luis, California 6 ? 0601 9/26 ? 6 Data starting on 9/26 0000Z
San Francisco, California 5 0615    9/26 0606 9/26 ? 6 Data starting on 9/26 0000Z
Monterey, California 9 0540    9/26 ? ? 6 Data starting on 9/26 0000Z

Harry Yeh translated the following damage report from a personal communication from Dr. Koshimura in Japan:
1. Port of Tokachi: more than 10 motor vehicles parked at the port where washed away into the sea by the tsunami.
No human casualty was reported.
2. Kushiro: two fishing boats were capsized.
3. Erimo-cho: A small car was washed away into the sea. The car was driven by an individual
who came to the port to check his fishing boat. No casualty was reported.

The following information was received from the Japan Meteorological Agency:

Tide gage site Maximum Observed Wave Amplitude (cm 0-p)
Kushiro, Japan 98 at 2018 GMT
Nemurohanasaki, Japan 90 at 2040 GMT
Miyako, Japan 57 at 2044 GMT
Ofunato, Japan 22 at 2049 GMT
Hachinohe, Japan 63 at 2053 GMT
Oshikaayukawa, Japan 16 at 2104 GMT
Hakodate, Japan 30 at 2121 GMT
Urakawa, Japan 129 at 2124 GMT
Iwakionahama, Japan 12 at 2124 GMT
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