Sea Ledger, August 1999
1999-08-01 to 1999-08-31 · archive
- issued
- 331
- warning-days in force
- 6,477
- in force at month end
- 198
- sea × type cells
- 177
baseline: same month, previous 5 years — not available for this month (needs three fully collected reference months)
By type
| type | issued | warning-days | in force at end |
|---|---|---|---|
| Nav aids | 62 | 1,853.1 | 61 |
| Incidents | 46 | 494 | 17 |
| Surveys | 41 | 335.3 | 11 |
| Quakes | 36 | 110.3 | 1 |
| Exercises | 34 | 260.1 | 6 |
| Other | 23 | 627.6 | 20 |
| Cable ops | 23 | 453.4 | 13 |
| Icebergs | 21 | 115.5 | 4 |
| Derelicts | 18 | 152.5 | 4 |
| Missiles | 11 | 88.7 | 4 |
| Ordnance | 7 | 946.4 | 29 |
| Spills | 5 | 91 | 2 |
| Containers | 2 | 7.2 | 0 |
| Wrecks | 1 | 526.1 | 16 |
| Mines | 1 | 62.3 | 2 |
| War risk | 0 | 136.5 | 1 |
| Structures | 0 | 124 | 4 |
| Restricted | 0 | 31 | 1 |
| Volcanic | 0 | 62 | 2 |
By sea and type · 177 cells, most issued first
Cite: seahazards.com Sea Ledger, 1999-08, retrieved 2026-09-03
Not for navigation. Warning-days = days each warning was in force within the month, summed. Only warnings we display are counted; the ratio compares warnings issued with the mean of the reference months.