Exercises

Hazardous operations 241200Z to 242000Z sep, alternate 271200Z to 272000Z, 291200Z to 292000Z sep and…

North Pacific Ocean · NAVAREA XII 513/21

What this record establishes

Archived notice · 2021-09-24 20:01Z

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) · SEA RANGE OTC 171741Z SEP 21.. Issued 2021-09-19 03:48Z. 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
North Pacific Ocean. The map shows an area described by the warning; the listed coordinate is its representative center. Check the original wording for limits and qualifications.

Related notices and cancellation links

Current notices and reporting history in the North Pacific Ocean →

Activity windows · 4 in this warning

opens (UTC)closes (UTC)locallength
2021-09-24 12:00Z2021-09-24 20:00Z—8 h
2021-09-27 12:00Z2021-09-27 20:00Z—8 h
2021-09-29 12:00Z2021-09-29 20:00Z—8 h
2021-10-01 12:00Z2021-10-01 20:00Z—8 h

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

issued
2021-09-19 03:48Z
status
Archived notice
self-cancels
2021-10-01 21:00Z
authority
SEA RANGE OTC 171741Z SEP 21.
NAVAREA
NAVAREA XII
issued by
SEA RANGE OTC
sea
North Pacific Ocean
position
33.401, -121.205
source
NGA MSI broadcast-warn JSON (archive, frozen 2024-05) · first seen 2026-08-17 13:38Z

Original warning text

EASTERN NORTH PACIFIC.
CALIFORNIA.
1. HAZARDOUS OPERATIONS 241200Z TO 242000Z SEP,
   ALTERNATE 271200Z TO 272000Z, 291200Z TO
   292000Z SEP AND 011200Z TO 012000Z OCT
   IN AREA BOUND BY
   33-20-20N 122-13-23W, 33-29-13N 121-36-22W,
   33-38-25N 120-21-11W, 33-22-33N 120-18-32W,
   33-13-22N 121-33-30W, 33-12-25N 122-11-54W.
2. CANCEL THIS MSG 012100Z OCT 21.

Reading this warning

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.
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.
Area bound by
Introduces a list of positions that are the corners of an area — the polygon the warning applies to.
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.

All warning terms →

Collected reports in this area · military exercises

1192 within 180 nm since 1999 · 35 in the last 12 months · 0 listed in force now

99
00
05
10
15
20
25
26

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

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

Worldwide in the collected sources

9 military exercises listed in force · see all

Record snapshot 2026-10-02 21:37Z; 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.