Within a radius of
A circular area — every position within a stated distance of a point.
"WITHIN 2 MILES OF 36-20.5N 015-12.3E" defines a circle around a point: a detonation site, a volcano, a wreck, a drilling rig. Radius-based areas are the simplest to write and to check against a position, and seahazards draws them as circles on the map.
Distances in warnings are normally nautical miles unless metres or cables are stated. A cable is a tenth of a nautical mile, about 185 metres.
What the archive shows
11,007 messages in this archive use “Within a radius of”, the earliest issued 1976-05-12 and the latest 2026-09-23. 9 of them are in force in the latest lists we collected. A hazard reported again and again counts once per message.
The largest yearly count is 2015, with 573 messages. Collection is incomplete between 2024-05 and 2026-08-17, so 2024, 2025 and 2026 are not comparable with fully collected years.
Exercises accounts for 7,432 of 11,007 recorded messages (68%), the largest warning type group in this selection.
Located messages that use it fall in 73 sea areas; the most frequent are North Pacific Ocean (2,720), North Atlantic Ocean (1,361) and Bay of Bengal (813).
Its use is spread fairly evenly through the year: the busiest month, September, has 1,068 messages and the quietest, February, 816.
By warning series: HYDROPAC 5,585, HYDROLANT 3,345, NAVAREA XII 1,285 and NAVAREA IV 687, and 5 more.
Messages using it, by year of issue
By month of issue, all years
Where it appears · 73 sea areas
- North Pacific Ocean 2,720
- North Atlantic Ocean 1,361
- Bay of Bengal 813
- Philippine Sea 773
- South Atlantic Ocean 741
- Arabian Sea 590
- Laccadive Sea 417
- South China Sea 385
- Mediterranean Sea - Eastern Basin 312
- North Sea 233
- Coral Sea 228
- South Pacific Ocean 192
In force now · 9
- NAVAREA XI 401/26 · Volcanic · Philippine Sea2026-09-08 · in force
…SHIMA LOCATION:27-14.6N 140-52.7E INFLUENCE OF ERUPTION IS EXPECTED WARNING WITHIN A RADIUS OF 0.6 MILES. CANCEL 0488/20.
080200UTC issued at 080200UTC sep 2026 volcanic warning volcano name:nishino shima LOCATION:27-14.6N… → - UKWZ 501/26 · Exercises · North Atlantic Ocean2026-08-17 · in force
…WEAPONS FIRINGS IN PROGRESS DAILY BETWEEN 0700 UTC AND 1700 UTC, 18 TO 21 AUG, IN AREA WITHIN 17 MILES OF 57-24.9N 007-59.7W. 2. THIS IS AN EXTREMELY HAZARDOUS AREA AND MARINERS ARE REQUESTED TO…
Live weapons firings in progress daily between 0700 UTC and 1700 UTC, 18 to 21 aug, in area within 17 miles… → - HYDROPAC 1873/26 · Cable ops · Tasman Sea2026-06-29 · in force
…SEA. AUSTRALIA. CABLE OPERATIONS IN PROGRESS UNTIL FURTHER NOTICE BY CABLESHIP RESPONDER WITHIN FIVE MILES OF TRACKLINE JOINING 38-19.86S 144-19.61E, 39-06.11S 145-33.18E, 39-17.45S 146-22.33E,…
Cable operations in progress until further notice by cableship responder within five miles of trackline… → - HYDROPAC 1585/26 · Cable ops · Great Australian Bight2026-05-30 · in force
…AUSTRALIA. CABLE OPERATIONS IN PROGRESS UNTIL FURTHER NOTICE BY CABLESHIP DEPENDABLE WITHIN TEN MILES OF TRACKLINE JOINING 38-25.00S 144-28.00E, 38-28.00S 144-28.00E, 38-22.00S 144-24.00E,…
Great australian bight → - HYDROLANT 237/26 · Missiles · Aegean Sea2026-02-03 · in force
…026-12.00E, 36-16.00N 026-40.00E, 35-36.00N 026-41.00E, 35-31.00N 024-11.00E. B. WITHIN ONE MILE OF 35-32.00N 024-13.00E. C. WITHIN ONE MILE OF 35-36.33N 024-10.00E. 2. CANCEL THIS MSG…
Missile operations 0530Z to sunset daily every wednesday thru saturday until 14 jun and 16 seb thru 31 dec… → - HYDROPAC 1415/25 · Restricted · Persian Gulf2025-06-01 · in force
PERSIAN GULF. KUWAIT. DNC 10. NAVIGATION PROHIBITED UNTIL FURTHER NOTICE IN AREA WITHIN 600 METERS OF 29-13.10N 048-44.42E.
Navigation prohibited until further notice in area within 600 meters of 29-13.10N 048-44.42E →
How it reads in recent messages
- HYDROLANT 1882/26 · Exercises · South Atlantic Ocean2026-09-23
SOUTH ATLANTIC. BRAZIL. 1. HAZARDOUS OPERATIONS 281100Z TO 291800Z SEP IN AREA WITHIN TEN MILES OF 14-22.00S 038-34.00W. 2. CANCEL THIS MSG 291900Z SEP 26.
Hazardous operations 281100Z to 291800Z sep in area within ten miles of 14-22.00S 038-34.00W → - HYDROPAC 2754/26 · Exercises · Philippine Sea2026-09-23
…GUAM. 1. HAZARDOUS OPERATIONS 0100Z TO 1300Z DAILY 28 THRU 30 SEP AND 01 OCT IN AREAS WITHIN THREE MILES OF: A. 13-27.00N 145-08.00E. B. 13-42.00N 144-36.00E. 2. CANCEL THIS MSG 011400Z OCT 26.
Hazardous operations 0100Z to 1300Z daily 28 thru 30 sep and 01 oct in areas within three miles of: a.… → - NAVAREA II 338/26 · Exercises · North Atlantic Ocean2026-09-22
CAP BLANC. SPECIAL OPERATIONS. FIRING EXERCISE. WITHIN 20 MILES OF: DELTA 23-35N 017-00W BETWEEN 270 AND 360 DEGREES NAVIGATE WITH CAUTION RESTRICTED AREA
Special operations → - NAVAREA XII 653/26 · Exercises · North Pacific Ocean2026-09-21
NORTH PACIFIC. CALIFORNIA. 1. HAZARDOUS OPERATIONS 271300Z TO 272300Z SEP IN AREA WITHIN ONE MILE OF 32-52.80N 118-17.70W. 2. CANCEL THIS MSG 280001Z SEP 26.
Hazardous operations 271300Z to 272300Z sep in area within one mile of 32-52.80N 118-17.70W → - NAVAREA XII 656/26 · Exercises · North Pacific Ocean2026-09-21
NORTH PACIFIC. CALIFORNIA. 1. HAZARDOUS OPERATIONS 281300Z TO 282300Z SEP IN AREA WITHIN ONE MILE OF 32-52.80N 118-17.70W. 2. CANCEL THIS MSG 290001Z SEP 26.
Hazardous operations 281300Z to 282300Z sep in area within one mile of 32-52.80N 118-17.70W → - NAVAREA XII 651/26 · Exercises · North Pacific Ocean2026-09-21
NORTH PACIFIC. CALIFORNIA. 1. HAZARDOUS OPERATIONS 251300Z TO 252300Z SEP IN AREA WITHIN ONE MILE OF 32-52.80N 118-17.70W. 2. CANCEL THIS MSG 260001Z SEP 26.
Hazardous operations 251300Z to 252300Z sep in area within one mile of 32-52.80N 118-17.70W → - NAVAREA XII 650/26 · Exercises · North Pacific Ocean2026-09-21
NORTH PACIFIC. CALIFORNIA. 1. HAZARDOUS OPERATIONS 261300Z TO 262300Z SEP IN AREA WITHIN ONE MILE OF 32-52.80N 118-17.70W. 2. CANCEL THIS MSG 270001Z SEP 26.
Hazardous operations 261300Z to 262300Z sep in area within one mile of 32-52.80N 118-17.70W → - NAVAREA XII 649/26 · Exercises · North Pacific Ocean2026-09-21
NORTH PACIFIC. CALIFORNIA. 1. HAZARDOUS OPERATIONS 241300Z TO 242300Z SEP IN AREA WITHIN ONE MILE OF 32-52.80N 118-17.70W. 2. CANCEL THIS MSG 250001Z SEP 26.
Hazardous operations 241300Z to 242300Z sep in area within one mile of 32-52.80N 118-17.70W →
Earliest in the archive
- NOAAORR-6229 · Spills · North Atlantic Ocean1976-05-12
…Dense clouds of smoke were blown over the town of La Coruña. A safety zone one mile in radius [...] 2. THREAT: OIL. COMMODITY: LIGHT ARABIAN CRUDE OIL, BUNKER FUEL. MAXIMUM POTENTIAL…
La coruña, spain →
Often in the same message
Related terms
- Area bound by
- Introduces a list of positions that are the corners of an area — the polygon the warning applies to.
- Wide berth requested
- Keep well clear — or, when a distance is given ("TWO MILE BERTH REQUESTED"), at least that far away.
- Safety zone / exclusion zone
- An area ships must stay out of, or may only enter with permission, for safety or security.
- 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.
Counts cover the messages in this archive that use the term, recounted 2026-09-24; see coverage for what is collected and since when. Not for navigation — follow official NAVAREA and coastal broadcasts.