Perth Tropical Cyclone Warning Centre

The 2000/2001 tropical cyclone and wet season outlook for North West Australia

Issued October 2000

Following the La Niña conditions during last summer, there was a return to more neutral conditions during the winter months. The Southern Oscillation Index (SOI) fell to near zero during early winter, however August and September SOI values again showed a rising trend. The SOI value for September was +10 compared with the value of zero a year ago. Sea surface temperatures off northwestern Australia are slightly warmer than normal at this time of the year.

Graph of the Southern Oscillation Index - January 1995 to September 2000

The outlook for the coming tropical cyclone season is based on climate model predictions of near neutral conditions persisting for the next 6 months.

Tropical cyclones

  • An average or slightly above average season with 4-6 cyclones likely to form off northwest Australia.
  • Highest risk of cyclone activity from January through to March.
  • The likelihood of 2 or 3 coastal impacts.
  • At least one severe tropical cyclone coastal impact during the season.
  • The likelihood of 1 or 2 tropical cyclones forming off the northwest coast before Christmas and there is some risk of one of these impacting the coast (most likely the Kimberley or Eighty Mile Beach).

Rainfall

The National Climate Centre's outlook for total November-January rainfall shows increased potential for above average totals in both the tropical north of Australia and in the southwest of W.A. (see map below). The chances are generally around 60 to 65% in these areas, with the highest forecast reliability being in the Northern Territory. Moderate outlook skill is also shown in southeast Queensland and NSW, but elsewhere it is low. Elsewhere the chances of wetter than average conditions don't vary greatly from 50%, although they are a little above in most cases.

Chance of exceeding median seasonal rainfall - November 2000 to January 2001 (from the Seasonal Climate Outlook, issued 12th October 2000)

Further enquires on the tropical cyclone outlook to:
Barry Hanstrum,
Severe Weather Section, Bureau of Meteorology, Perth
Tel: (08) 9263 2282, Fax: (08) 9263 2297
e-mail: b.hanstrum@bom.gov.au

For more information regarding the rainfall outlook contact the National Climate Centre during normal office hours from 8:45am to 5:30pm (EDT) Monday to Friday.

Grant Beard - Tel: (03) 9669 4527
e-mail: g.beard@bom.gov.au