The Bureau of Meteorology’s latest three month seasonal outlook released this morning predicts a drier than normal season for large parts of eastern Australia, and a wetter than normal season for parts of western WA and southern Tasmania.
The chances of a wetter or drier than normal season are roughly equal over the remainder of the country, according to the outlook for January to March 2014.
The chances of exceeding median rainfall during the next three months are rated at 30 to 40pc over most of Queensland, parts of the eastern NT, most of NSW and northeast Victoria.
In other words, the Bureau says the chances of below average rainfall are 60 to 70pc over these areas.
“So, for every 10 summer outlooks with similar odds to these, about three or four of them would result in above-average rainfall over these areas, while about six or seven would be below average.”
Conversely, the chance of exceeding the median rainfall is greater than 60pc over parts of western WA and most of Tasmania.
The chance of receiving a wetter or drier than normal January to March period is roughly equal (i.e. close to 50pc) over the remainder of the country.
The Bureau says the El Niño-Southern Oscillation (ENSO) remains neutral, with the majority of atmospheric and oceanic indicators close to their long-term average. Dynamical models surveyed by the Bureau suggest ENSO-neutral conditions are likely to persist at least for the austral summer and early autumn. This means there is no strong shift in the odds from the tropical Pacific in this outlook.
Although the Indian Ocean Dipole has limited impact upon Australia during the months from December to April, the broad area of warmer than average sea surface temperatures across the central Indian Ocean has been shown to influence the climate over large parts of Australia at this time of year.
Lower surface pressures are likely to bring cooler and potentially wetter conditions to parts of southern Australia (such as Tasmania and parts of southwest WA) early in the outlook period.
For northern regions, tropical Australian sea surface temperatures are currently average to slightly cooler than average, and are expected to remain that way over the forecast period. Weak to moderate tropical activity (cloud and rainfall associated with the Madden-Julian Oscillation) is expected in the first month.
National temperature outlook
The chances of the January to March maximum temperature exceeding the long-term median maximum temperature are greater than 60pc over the northeastern half of the country (click on maps below to view). Odds increase to greater than 70pc over the Top End of the NT, central and southern Queensland, and parts of the NSW coast.
Conversely, the chances of exceeding the median maximum temperature is less than 40pc over southwest WA, the southwest coast of Victoria and northern Tasmania.
The chances of receiving a cooler or warmer than normal January to March is roughly equal (i.e. close to 50pc) over the remainder of the country.
The chances that the average minimum temperature for January to March will exceed the long-term median are greater than 60pc over the Kimberley in WA, the NT, Queensland, and northeast NSW.
Odds increase to greater than 70pc over the northern Kimberley and the Top End of the NT, parts of central and southern Queensland, and the far northeast of NSW.
The chances of exceeding the median minimum temperature is less than 40pc over the far southeast of SA, southern Victoria and northern Tasmania. In other words, the chances of cooler than normal night-time temperatures is greater than 60pc.
Source: Bureau of Meteorology
Click on maps below to view in larger format