Cyclone Atu (2011)
Cyclone Atu reached Category 4 in the South Pacific between February 16, 2011 and February 27, 2011, with a lowest pressure of 937 mb.
Track and intensity
The whole track of Cyclone Atu, colored by strength, with the other storms of the 2011 season in the same basin behind it, and its wind and pressure hour by hour. Every fix is in the track table below.
The storm
- Basin
- South Pacific
- Dates
- February 16, 2011 to February 27, 2011
- Peak strength
- Category 4, 115 kt (132 mph)
- Lowest pressure
- 937 mb (27.67 inHg)
- Landfall
- No; closest approach 128 km (80 mi)
- Accumulated cyclone energy
- 17.1
- Identifier
- SH172011
Deaths and damage
No source this site reads carries a casualty or damage figure for this storm.
Track
| Time (UTC) | Position | Wind | Pressure | Status |
|---|---|---|---|---|
| Feb 16, 18:00 | 13.5S 171.0E | 15 kt | 1003 mb | Not reported |
| Feb 17, 00:00 | 13.5S 170.7E | 20 kt | 1007 mb | Disturbance |
| Feb 17, 06:00 | 13.8S 170.3E | 20 kt | 1007 mb | Disturbance |
| Feb 17, 12:00 | 14.0S 169.9E | 20 kt | 1007 mb | Disturbance |
| Feb 17, 18:00 | 14.1S 169.5E | 25 kt | 1004 mb | Disturbance |
| Feb 18, 00:00 | 14.3S 169.2E | 25 kt | 1004 mb | Disturbance |
| Feb 18, 06:00 | 14.8S 169.3E | 30 kt | 1000 mb | Tropical depression |
| Feb 18, 12:00 | 15.2S 169.3E | 35 kt | 996 mb | Tropical storm |
| Feb 18, 18:00 | 15.5S 169.3E | 35 kt | 996 mb | Tropical storm |
| Feb 19, 00:00 | 15.9S 169.1E | 45 kt | 989 mb | Tropical storm |
| Feb 19, 06:00 | 16.2S 168.9E | 50 kt | 985 mb | Tropical storm |
| Feb 19, 12:00 | 16.5S 168.9E | 55 kt | 982 mb | Tropical storm |
| Feb 19, 18:00 | 16.7S 169.1E | 60 kt | 978 mb | Tropical storm |
| Feb 20, 00:00 | 16.8S 169.3E | 75 kt | 967 mb | Typhoon |
| Feb 20, 06:00 | 17.0S 169.5E | 90 kt | 956 mb | Typhoon |
| Feb 20, 12:00 | 17.2S 169.6E | 100 kt | 948 mb | Typhoon |
| Feb 20, 18:00 | 17.5S 169.7E | 115 kt | 937 mb | Typhoon |
| Feb 21, 00:00 | 17.9S 169.9E | 110 kt | 941 mb | Typhoon |
| Feb 21, 06:00 | 18.5S 170.2E | 105 kt | 944 mb | Typhoon |
| Feb 21, 12:00 | 19.1S 170.6E | 100 kt | 948 mb | Typhoon |
| Feb 21, 18:00 | 19.9S 171.2E | 100 kt | 948 mb | Typhoon |
| Feb 22, 00:00 | 21.2S 171.8E | 95 kt | 952 mb | Typhoon |
| Feb 22, 06:00 | 22.6S 172.1E | 95 kt | 952 mb | Typhoon |
| Feb 22, 12:00 | 23.9S 172.7E | 95 kt | 952 mb | Typhoon |
| Feb 22, 18:00 | 25.4S 173.7E | 90 kt | 959 mb | Typhoon |
| Feb 23, 00:00 | 26.9S 174.8E | 80 kt | 963 mb | Typhoon |
| Feb 23, 06:00 | 28.5S 176.4E | 75 kt | 967 mb | Typhoon |
| Feb 23, 12:00 | 30.0S 177.8E | 70 kt | 970 mb | Typhoon |
| Feb 23, 18:00 | 31.3S 179.4E | 60 kt | 978 mb | Tropical storm |
| Feb 24, 00:00 | 32.4S 178.8W | 50 kt | 985 mb | Tropical storm |
| Feb 24, 06:00 | 33.2S 176.9W | 45 kt | 989 mb | Tropical storm |
| Feb 24, 12:00 | 33.8S 175.3W | 40 kt | 993 mb | Tropical storm |
| Feb 24, 18:00 | 34.1S 173.8W | 35 kt | 996 mb | Tropical storm |
| Feb 25, 00:00 | 34.7S 172.4W | 35 kt | 996 mb | Extratropical |
| Feb 25, 06:00 | 35.8S 171.4W | 35 kt | 996 mb | Extratropical |
| Feb 25, 12:00 | 37.0S 187.0E | 40 kt | 981 mb | Not reported |
| Feb 25, 18:00 | 39.0S 187.0E | 40 kt | 981 mb | Not reported |
| Feb 26, 00:00 | 40.7S 188.3E | 40 kt | 980 mb | Not reported |
| Feb 26, 06:00 | 43.0S 189.0E | 40 kt | 982 mb | Not reported |
| Feb 26, 12:00 | 45.0S 189.0E | 40 kt | 988 mb | Not reported |
| Feb 26, 18:00 | 47.0S 189.0E | 40 kt | 986 mb | Not reported |
| Feb 27, 00:00 | 47.0S 189.0E | 40 kt | 987 mb | Not reported |
| Feb 27, 06:00 | 51.0S 191.0E | 40 kt | 985 mb | Not reported |
| Feb 27, 12:00 | 52.0S 193.0E | 40 kt | 988 mb | Not reported |
Other South Pacific storms of 2011
What this means
A best track is the record a warning agency settles on after the storm, not what it said at the time: position, maximum sustained wind and central pressure every six hours, revised against every observation that came in later. Category is the Saffir-Simpson scale, which runs from Category 1 at 64 kt to Category 5 at 137 kt and reads wind only, so it says nothing about surge or rain. Accumulated cyclone energy adds up the square of the wind through the storm's life, so it counts strength and duration together.
Sources
Storm history from NOAA NCEI’s International Best Track Archive for Climate Stewardship (IBTrACS), which merges the official best track of every warning agency. Live storms, cones, watches and warnings from the National Hurricane Center and the Central Pacific Hurricane Center. Archived radar from NOAA’s Level II archive.