Friday 2 October 2009

MEDIA RELEASE - NORTHERN TERRITORY 2009-10 TROPICAL CYCLONE SEASON OUTLOOK

No room for complacency with El Niño cyclones

The Bureau of Meteorology in Darwin has released its 2009-10 Cyclone Season Outlook for the waters surrounding the Northern Territory. The outlook is for near neutral conditions, with the first cyclone likely to occur in January.

Gordon Jackson, supervising meteorologist in the Tropical Cyclone Warning Centre in Darwin, said that during a normal El Niño, a slow start to the cyclone season might be expected. “That is probably true for Australia overall this season,” Mr Jackson said, “but this El Niño is a bit unusual. There are mixed signals from the ocean and the atmosphere, and things are a bit harder to read.

“We want to emphasise to all Territorians living near the coast that there is no room for complacency; the cyclone season starts on 1 November and it is time to get ready. Many Territorians would remember that TC Helen, though relatively weak, caused significant damage and disruption around Darwin last year. And Severe TC Monica, in 2007, devastated the coastline west of Maningrida when it came ashore, before heading inland and seriously damaging Oenpelli and Jabiru.”

Oceanic signals suggest a moderate strength El Niño event, while atmospheric signals are less clear and more indicative of near-neutral conditions. Almost all available indicators suggest that there is little scope for the El Niño to develop further during the coming cyclone season, which runs from 1 November to 30 April next year. Based on the current phase of the El Niño-Southern Oscillation atmospheric circulation system, it is expected that tropical cyclone activity will be near average over the northern region in the coming season.

Details of the outlook for the 2009-10 tropical cyclone season for the northern region:

• An early cyclone (November or early December) is unlikely, though it cannot be ruled out. It is more likely that the first cyclone will occur in January.
• On average, two to three cyclones form in the waters surrounding the Northern Territory each season. However, cyclone numbers in past seasons have ranged from none to as many as five.
• The Gulf of Carpentaria tends to have the most cyclone activity, though cyclones can still occur anywhere in the waters surrounding the Northern Territory. In past seasons, with similar conditions, cyclones occurred 50 per cent more often in the Gulf than in the waters to the north or west of the Top End.
• There is also a 50 per cent chance of a severe tropical cyclone (Category 3 or greater) forming during the season. If a severe cyclone forms this season, it is more likely to affect the Gulf of Carpentaria.

The northern region incorporates the eastern Timor Sea, Arafura Sea and the Gulf of Carpentaria.

More information

• Gordon Jackson, tel: (08) 8920 3872, mob: 0417 897 324
• Greg Browning, tel: (08) 8920 3870, e-mail: ntsevere@bom.gov.au
• Status of El Niño-Southern Oscillation: http://www.bom.gov.au/climate/enso
• Map of historical TC distributions in El Niño years: http://www.bom.gov.au/jsp/ncc/climate_averages/tropical-cyclones/index.jsp
• Tropical cyclone warnings and information: http://www.bom.gov.au/weather/cyclone/