MAY STARTS OUT DRY - BUT DOES IT STAY THAT WAY?

Some interesting signals from the global climate models, with a mixed camp suggesting large parts of the country will be dry but coastal areas that have been hit hard by heavy rainfall could be in line for another round of potentially above average rainfall.


The overall pattern for the east coast is in line with climate averages. This is the wettest time of the year and these events do occur 1-2 times every year.


This year there has been prolific rainfall along the east coast and so any additional average to above average rainfall will be difficult to manage.


So with that the trends don't look positive for the east coast off current guidance, but this is still some ways out and COULD change.


The latest Euro ensemble climate outlook for the country. This takes us to the end of May.

But there are some models that keep a large part of Australia in dry air and well below average rainfall - I am still inclined to lean that way for inland areas.




The reason being the potential for blocking patterns to set up in the Tasman Sea, if easterly winds return in full flight, then the ability for moisture to be drawn in from the north and west are shunted but high pressure being stacked through southern WA or western SA. That stops anything meaningful developing for a good portion of the central interior where it has been dry.


In the above GFS model run - we are tracking the blocking pattern with fronts not making it to VIC and SA as freely as the Euro modelling. So that is something to consider with the ongoing climate outlooks, the impact of ongoing easterly winds and how they help to deflect the frontal weather moving in from the west.




The east coast under the Euro scenario will have to be on standby for further flooding with those anomalies of 125mm+ for the month over such a wide area which has been impacted by flooding already this year a cause for concern. That is an additional 100-200mm of rainfall above what one would normally receive so that is a lot of rainfall.


By contrast the brown shading through SA means many areas many have a dry month after a rainless April. Not great news for those in the region looking for something meaningful. GFS is more aggressive on this idea with a blocking pattern setting up over the region with high pressure remaining in place.


As I always say, these are the latest signals and this is latest analysis that will change. It is much better to refer to the medium and short term forecasts that I post here daily and then come back to these climate outlooks to compare.


The next CLIMATE UPDATE will be made on Friday with my full forecast charts for May.


For those that missed the last forecast here it is below for the month of May.





0 views0 comments