JUNE was quite a dry month for much of eastern Australia but it is likely that July will be quite the opposite.
All current modelling indicates that above average rainfall is likely to occur for much of the state for the remainder of winter, and it's likely that this pattern will continue into spring with a negative Indian Ocean Dipole correlating well to wetter springs than normal.
That, in combination with warm and above average ocean temperatures across around much of the continent, would support this scenario.
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It will also mean an increase in cloud cover which might see slightly below normal daytime (maximum) temperatures and slightly warmer than normal minimum temperatures.
Looking at the main indicators at present - in the Pacific cool water is continuing through large parts of the central to eastern Equatorial Pacific Ocean while generally warm water exists through the western Pacific.
This has all the hallmarks of a decreasing but lingering La Nina pattern.
Also, a pool of warm water 100-200m below the surface in the western Pacific is extending east where it's beginning to upwell and erode the surface cool water anomalies across the eastern half of the Pacific Ocean, thus breaking down - at least temporarily - the dominant La Lina pattern.
If this continues, then the Pacific will move into a neutral pattern shortly.
It is worth noting that the dominant easterly trade winds in the Pacific Ocean could promote the upwelling of renewed cooler water towards early to mid-spring and this could see the risk of a rare triple La Nina patterns for late spring and summer again but this remains speculative at this stage.
The Pacific is at its weakest influence on weather in eastern Australia in winter. Rainfall at this time is more often dominated by the IOD (and even the Southern Annular Mode).
It remains increasingly likely that the negative IOD in the Indian Ocean will continue for the remainder of winter and spring. Recent trends in the Indian Ocean have pointed more strongly towards a negative IOD occurring, with large amounts of warm water occurring across the eastern Indian Ocean.
This will continue to enhance rainfall prospects into at least spring.
The other aspect of increasing rainfall in the short term is the positive SAM phase.
It is unusual to have a prolonged positive SAM phase in winter, and it would be likely to see a return to more negative SAM phases during the second half of July which should see more normal winter conditions develop.
If north-west cloud bands still occur, they would favour rain in more inland areas of NSW as opposed to coastal areas.
