UNSETTLED spring weather is persisting over south-eastern Australia with local severe storms and some useful rains.
Uniformity of rainfall west of the divide has been lacking as there has been limited moisture infeed in upper and middle levels of the atmosphere from the north west (no north-west cloud bands) which would improve uniformity.
This is unlikely to change in the foreseeable future.
A positive Indian Ocean Dipole (IOD) as we have at the moment is never a good sign for south-eastern Australian rain events.
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However, its effects will only last until towards the end of the November when the influence of the northern monsoon starts to have an effect – hopefully.
The situation in the Pacific Ocean remains a little unclear.
An El Nino event seemed very likely some months back, but then things stagnated a little. In recent weeks the El Nino thresholds have been approached again and it is now slightly favoured that at least a weak El Nino event will develop by late spring and persist for a few months but not as long as originally thought.
As indicated previously developing and weak El Nino events do not always mean drier than normal weather.
They can also influence “storminess” and there have already been severe storms in parts of NSW and Queensland.
The chance of hail from these storms remains slightly higher than in an average season.
However, the situation can also bring occasional rain events and such events, although patchy and variable in places, are likely to persist for at least a few more weeks.
Temperatures have been surprisingly cool in recent weeks in many parts of south-eastern Australia, but the expected outlook is still for above average temperatures by late spring and during summer, with higher evaporation levels developing.
The long term outlook is for neutral conditions returning to the Pacific basin early in 2019 with near average rainfall more likely next year.
