Exercises

Hazardous operations 0800Z to 1800Z daily 26 thru 30 dec in area within ten miles of 23-34.28S 043-08.23W

South Atlantic Ocean · HYDROLANT 2925/23

What this record establishes

Archived notice · 2023-12-30 19:00Z

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) · NAVAREA V 573/23 210401Z DEC 23.. Issued 2023-12-21 04:23Z. 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: South Atlantic Ocean. The parsed report position is -23.571, -43.137 with a 10.0 nm radius. It is a position in the source message, not a live location. Check the original wording for limits and qualifications.

Current notices and reporting history in the South Atlantic Ocean →

Activity windows · 5 in this warning

opens (UTC)	closes (UTC)	local	length
2023-12-26 08:00Z	2023-12-26 18:00Z	—	10 h
2023-12-27 08:00Z	2023-12-27 18:00Z	—	10 h
2023-12-28 08:00Z	2023-12-28 18:00Z	—	10 h
2023-12-29 08:00Z	2023-12-29 18:00Z	—	10 h
2023-12-30 08:00Z	2023-12-30 18:00Z	—	10 h

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

issued: 2023-12-21 04:23Z
status: Archived notice
self-cancels: 2023-12-30 19:00Z
authority: NAVAREA V 573/23 210401Z DEC 23.
NAVAREA: NAVAREA V · named as the source of this relay
sea: South Atlantic Ocean
position: -23.571, -43.137 · r 10.0 nm
source: NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

WESTERN SOUTH ATLANTIC.
BRAZIL.
DNC 01.
1. HAZARDOUS OPERATIONS 0800Z TO 1800Z
   DAILY 26 THRU 30 DEC IN AREA WITHIN
   TEN MILES OF 23-34.28S 043-08.23W.
2. CANCEL THIS MSG 301900Z DEC 23.

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.
Hazardous operations: NGA's heading for activities that make an area dangerous — most often rocket launches, space debris and weapons firings, and some open-ended danger areas.
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.
CANCEL THIS MSG: The warning's own expiry: a line telling the reader when the message cancels itself.
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 · military exercises

654 within 180 nm since 1999 · 6 in the last 12 months · 1 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

Hazardous operations in progress until 060400Z jun 27 in area bound by 24-39.87S 042-29.30W, 24-39.78S…Exercises · 73.4 nm

Worldwide in the collected sources

28 military exercises listed in force · see all

Record snapshot 2026-10-02 00:56Z; source collection times vary.

Exercises

Gunnery, firing and naval exercise areas. All current military exercises →

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.