Seasonal Climate Outlook Message for October to January 2004

The bottom line

Climate Watch (Dated 23rd Oct)

Recent reports from both the United States Climate Prediction Centre www.cpc.ncep.noaa.gov/ and the Australian Bureau of Meteorology www.bom.gov.au/ highlight that a neutral sea temperature pattern continues to persist in the tropical Pacific Ocean.

Overall, very little net change has been observed in SST anomalies across the Pacific over the last couple of months. However, there has been some re-warming of sea surface temperatures in the central equatorial Pacific. Accompanying this pattern, strong westerly wind bursts have also returned (at least temporarily) to the equatorial Pacific.

At this time of the year this should not present any major problem. However, should westerly wind bursts persist for another two or three months then that may allow 'El Nino-like' conditions to return to the equatorial Pacific next winter.

As this is still some time away, we will monitor patterns in the equatorial Pacific on a monthly basis to determine what impact, if any, ongoing changes may have on the seasonal outlook. We will also provide more updated information on patterns in the Pacific over the coming months as it becomes relevant and available.

Ocean and coupled ocean/atmosphere forecast models (GCM's) give an indication as to likely ENSO development out to 9 months. Of 11 models that forecast out to February 2004, all indicate the continuation of a neutral sea surface temperature pattern.

Of the 9 models that forecast out to May 2004, 8 indicate a continuing neutral sea temperature pattern while 1 suggests the potential development of an El Nino (or warm) sea surface temperature pattern.

While it is positive news that the majority of these models highlight a continuing neutral SST pattern (rather than an El Nino pattern), given current ocean and atmospheric conditions our policy remains to recommend a cautious approach when considering the longer term (6-9months) outlook.

More details can be found at www.bom.gov.au/climate/ahead/ENSO-summary.shtml

The 30day average of the SOI has fallen since the start of the month and as of the 23rd October is minus 4.3. Daily recorded SOI updates are also available on 07 46881439.

Recent research has shown that with the recent SOI pattern there is an increased potential for severe storm activity (especially when compared with last year) including wind and hail across southern Queensland and northern NSW.

The latest version of 'Rainman StreamFlow' has also just been released. Many new features have been introduced and to highlight these advances free copies of this program that 'time out' in 12 months are available from Land and Water Australia on 1800 776 616.

Due to the size of the area covered, the information provided in this column is of a fairly broad nature. For those readers who require more specific climate information, try www.longpaddock.qld.gov.au or www.dpi.qld.gov.au/climate or contact us through the DPI Call Centre on 13 25 23.

Last updated: 22 October 2003