Discoloured water and submarine volcanic eruption continue near 24-17.2N 141-28.8E, North Pacific, Nanpo Shoto, at 140350Z June. Caution advised.
Philippine Sea · NAVAREA XI 207/23
What this record establishes
Listed in force
The latest collected record lists this warning as active. This is the status of the notice, not a live observation of conditions at the location.
- Source and dates
- Japan Coast Guard JHOD NAVAREA XI · Japan Coast Guard (JHOD). Issued 2023-06-14 12:00Z. First collected 2026-08-17 13:42Z; last seen in collection 2026-08-17 14:24Z. Collection dates record ingestion, not a new incident or a fresh field observation.
- Location covered
- Philippine Sea. The parsed report position is 24.287, 141.480. It is a position in the source message, not a live location. Check the original wording for limits and qualifications.
Related notices and cancellation links
These reports were linked by category and sea, with positions within 30 nautical miles and issue dates within 30 days of another report's recorded in-force span. Links can extend through other members, so the full group can cover a larger area or period. Proximity does not confirm that they describe one incident.
- NAVAREA XI 231/212021-07-13 · Listed in force
- HYDROPAC 2027/212021-07-13 · Cancelled notice
- NAVAREA XI 207/23 · this notice2023-06-14 · Listed in force
- HYDROPAC 3542/232023-11-10 · Cancelled notice
- HYDROPAC 3334/242024-10-23 · Cancelled notice
- HYDROPAC 2242/252025-09-02 · Listed in force
Current notices and reporting history in the Philippine Sea →
- issued
- 2023-06-14 12:00Z
- status
- Listed in force
- authority
- Japan Coast Guard (JHOD)
- NAVAREA
- NAVAREA XI
- issued by
- JAPAN COAST GUARD
- sea
- Philippine Sea
- position
- 24.287, 141.480
- nearest port
- Saipan · 595 nm
- source
- Japan Coast Guard JHOD NAVAREA XI · first seen 2026-08-17 13:42Z
Original warning text
NORTH PACIFIC, NANPO SHOTO. DISCOLOURED WATER OBSERVED IN VICINITY OF 24-17.2N 141-28.8E AT 140350Z JUN. SUBMARINE VOLCANIC ERUPTION CONTINUE. VESSELS REQUESTED TO BE CAUTION ADVISED. CANCEL 0110/22.
Reading this warning
- Discoloured water
- Patches of unusually coloured sea — often a sign of a submarine volcano or of a shoal.
- Position (degrees and minutes)
- How warnings write positions: degrees, a hyphen, then minutes, with N/S and E/W — 49-40.8N 003-43.8W.
- Date-time group (DTG)
- A compact UTC timestamp — day, hour and minute followed by Z — such as 201500Z for the 20th at 15:00 UTC.
- Volcanic activity
- An erupting or restless volcano near or under the sea, with a keep-clear radius around it.
Nearest volcano
Fukutoku-Okanoba · 1 km
Conditions at the position · now
loading…
MET Norway · NOAA WaveWatch III · HYCOM · GEBCO 2020 · model data at the centroid, not an observation
Collected reports in this area · volcanic activity
57 within 180 nm since 2001 · 0 in the last 12 months · 5 listed in force now
Counts include repeat notices about the same situation. NGA archive coverage ends 2024-05; live collection began 2026-08-17. The period between them is incomplete. An empty year is not evidence that no hazards occurred.
- Volcanic activity reported at io-to in vicinty of 24-45.00N 141-17.3E2025-09-02
- Volcanic activity reported in area within 400 meters of 24-45.44N 141-19.60E2024-10-23
- Volcanic activity reported in area within 400 meters of 24-45.44N 141-19.60E at 100428Z nov2023-11-10
- Discolored water reported in vicinity 25-27.10N 141-14.50E at 140425Z jun2023-06-14
- Discoloured water observed in vicinity of 25-27.1N 141-14.5E at 140425Z jun2023-06-14
- Discolored water reported in vicinity 25-27.10N 141-14.50E at 110433Z may2023-05-12
Month of issue in the collected archive
All available years combined. Uneven collection and repeat bulletins affect these counts; this chart does not measure the seasonality or probability of incidents.
Nearby notices listed in force · within 120 nm
Worldwide in the collected sources
12 volcanic activity listed in force · see all
Record snapshot 2026-09-25 21:18Z; source collection times vary.
Volcanic
Submarine eruptions, discoloured water, pumice rafts. All current volcanic activity →
Not for navigation. This is a re-rendering of an official navigational warning for awareness; mariners must use official NAVAREA broadcasts and their national MSI service.