Discoloured water observed within about 0.7 miles of 27-13.6N 140-55.3E in North Pacific, Nanpo Shoto, at 120643Z Oct.
Philippine Sea · NAVAREA XI 325/21
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 2021-10-12 10:00Z. 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 27.227, 140.922. 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.
- HYDROPAC 3739/202020-12-18 · Archived notice
- NAVAREA XI 488/202020-12-18 · Cancelled notice
- NAVAREA XI 325/21 · this notice2021-10-12 · Listed in force
- HYDROPAC 2908/212021-10-12 · Archived notice
- HYDROPAC 2909/212021-10-12 · Archived notice
- NAVAREA XI 326/212021-10-13 · Listed in force
Current notices and reporting history in the Philippine Sea →
- issued
- 2021-10-12 10:00Z
- status
- Listed in force
- authority
- Japan Coast Guard (JHOD)
- NAVAREA
- NAVAREA XI
- issued by
- JAPAN COAST GUARD
- sea
- Philippine Sea
- position
- 27.227, 140.922
- nearest port
- Shimizu · 484 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. WITHIN ABOUT 0.7 MILES OF 27-13.6N 140-55.3E AT 120643Z OCT. VESSELS REQUESTED TO BE CAUTION ADVISED.
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.
Nearest volcano
Doyō Seamount · 50 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
87 within 180 nm since 1996 · 2 in the last 12 months · 7 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 in area within one mile of 27-14.60N 140-52.70E at 080200Z sep2026-09-08
- 080200UTC issued at 080200UTC sep 2026 volcanic warning volcano name:nishino shima LOCATION:27-14.6N…2026-09-08
- 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
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
- 080200UTC issued at 080200UTC sep 2026 volcanic warning volcano name:nishino shima LOCATION:27-14.6N…Volcanic · 2.5 nm
- Discoloured water observed in extending south for 5 miles, 2 mile wide, from 27-16.7N 140-56.6E at 120643Z octVolcanic · 3.3 nm
- Chichi shima, futami ko NR.3 light buoy, 27-04.9N 142-11.2E, L.LNav aids · 68.1 nm
- Discoloured water observed in vicinity of 25-27.1N 141-14.5E at 140425Z junVolcanic · 108 nm
Worldwide in the collected sources
12 volcanic activity listed in force · see all
Record snapshot 2026-09-29 13:13Z; 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.