Volcanic

Possible pumices adrift in vicinity of trackline joining 30-41.00N 139-51.00E, 30-24.00N 139-45.00E,…

Philippine Sea · HYDROPAC 3336/23

What this record establishes

Archived notice · 2023-10-20 15:31Z

This notice comes from the historical archive. Its archived status does not establish when or how the reported situation ended.

Source and dates
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · NAVAREA XI 361/23 201003Z OCT 23.. Issued 2023-10-20 10:41Z. First collected 2026-08-17 13:38Z; last seen in collection 2026-08-17 15:46Z. Collection dates record ingestion, not a new incident or a fresh field observation.
Location covered
Philippine Sea. The map shows the reported line or operation extent; it is not a vessel track. 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.

  1. HYDROPAC 3336/23 · this notice2023-10-20 · Archived notice
  2. HYDROPAC 3339/232023-10-20 · Archived notice
Compare all 2 notices, changes and original texts →

Current notices and reporting history in the Philippine Sea →

issued
2023-10-20 10:41Z
status
Archived notice
authority
NAVAREA XI 361/23 201003Z OCT 23.
NAVAREA
NAVAREA XI · named as the source of this relay
sea
Philippine Sea
position
30.331, 139.726
source
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

PHILIPPINE SEA.
JAPAN.
DNC 12.
POSSIBLE PUMICES ADRIFT IN VICINITY OF
TRACKLINE JOINING
30-41.00N 139-51.00E, 30-24.00N 139-45.00E,
30-17.00N 139-44.00E, 30-13.00N 139-40.00E,
30-10.00N 139-40.00E, 30-05.00N 139-38.00E,
29-59.00N 139-36.00E. AT 200525Z OCT.

Reading this warning

DNC (Digital Nautical Chart)
A reference to one of the regions of NGA's Digital Nautical Chart, used to tell the reader which charts a warning affects.
Adrift
Loose and moving with wind and current — a vessel, container, buoy, log or anything else no longer secured.
Track line joining
Introduces a route through a series of positions — a cable route, a tow's track or a survey line.
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.

All warning terms →

Collected reports in this area · volcanic activity

12 within 180 nm since 2001 · 0 in the last 12 months · 2 listed in force now

01
05
10
15
20
24

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.

Month of issue in the collected archive

J
F
M
A
M
J
J
A
S
O
N
D

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 2026-10-01 18:06Z; 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.