Surveys

Underwater operations 080900Z apr to 030900Z may by M/V atlantis and submersible alvin in: a. area within 40…

Gulf of California · NAVAREA XII 230/24

What this record establishes

Archived notice · 2024-05-03 10:00Z

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) · WHOI 0/24 052032Z APR 24.. Issued 2024-04-05 20:40Z. 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: Gulf of California. The map shows an area described by the warning; the listed coordinate is its representative center. Check the original wording for limits and qualifications.

Current notices and reporting history in the Gulf of California →

Activity windows · 1 in this warning

opens (UTC)	closes (UTC)	local	length
2024-04-08 09:00Z	2024-05-03 09:00Z	—	600 h

Parsed from the warning text; outside these windows the area is normally not active, but the warning stays in force until cancelled.

issued: 2024-04-05 20:40Z
status: Archived notice
self-cancels: 2024-05-03 10:00Z
authority: WHOI 0/24 052032Z APR 24.
NAVAREA: NAVAREA XII
issued by: WHOI
sea: Gulf of California
position: 27.291, -111.533
vessel: M/V ATLANTIS · 37 messages
source: NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

GOLFO DE CALIFORNIA.
MEXICO.
1. UNDERWATER OPERATIONS 080900Z APR TO 030900Z MAY
   BY M/V ATLANTIS AND SUBMERSIBLE ALVIN IN:
   A. AREA WITHIN 40 MILES OF 23-52.50N 108-44.70W.
   B. AREA WITHIN 40 MILES OF 27-15.00N 111-32.00W.
   WIDE BERTH REQUESTED.
2. CANCEL THIS MSG 031000Z MAY 24.

Reading this warning

Underwater operations: Divers or remotely operated vehicles are working below a vessel that cannot easily move out of the way.
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.
Within a radius of: A circular area — every position within a stated distance of a point.
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.
Wide berth requested: Keep well clear — or, when a distance is given ("TWO MILE BERTH REQUESTED"), at least that far away.
CANCEL THIS MSG: The warning's own expiry: a line telling the reader when the message cancels itself.

All warning terms →

Collected reports in this area · survey operations

5 within 180 nm since 2010 · 0 in the last 12 months · 0 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.

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

No other collected notice is currently listed in force within this radius. This does not establish safe conditions.

Worldwide in the collected sources

55 survey operations listed in force · see all

Record snapshot 2026-10-01 06:08Z; source collection times vary.

Surveys

Hydrographic and scientific survey vessels, often towing long arrays. All current survey operations →

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.