The pattern of seasonal maximum temperature odds across Western Australia is
mainly a result of the La Niña pattern of cooler than average temperatures along the
Averaged over January to March, the chances are between 60 and 65% for above-normal maximum
temperatures over much of the southern one-third of WA (see map).
So for every ten years with ocean patterns like the current, about six
March quarters are expected to be warmer than average in southern WA,
with about four being cooler.
Outlook confidence is related to how consistently the Pacific and Indian
Oceans affect Australian temperatures. During the March quarter, history
shows the effect on maximum temperatures to be moderately consistent
in a broad zone about a line joining Port Hedland and Esperance, and about the far
northeast coast. The effect is generally very weak along the west coast and
throughout the northeast interior (see background information).
Minimum temperatures for the March quarter are favoured to be warmer than normal across
much of Western Australia, the main exceptions being the southeast and parts
of the west (see map). The chances of increased
overnight warmth (averaged over the coming three months) are between 60
and 70% over large areas of WA. Across the rest of the State, the chances of the
seasonal mean minimum being above the long-term average are between 50 and 60%.
History shows the oceans' effect on WA's minimum temperatures during the March quarter
to be moderately consistent in the north, along parts of the west coast and
some of the southeast. Elsewhere the effect is weakly to very weakly consistent.