Moderate La Nina to develop by Summer

Earlier in the year back in January we predicted most of OZ would see a dry Winter and Spring once the monsoon retreated back north and sad to say it has been the case most of us especially in Queensland, NSW, and most inland areas of SA, WA and NT.

Regular cold fronts has produced some decent rain over parts of southern SA and parts of Victoria as well as south west WA and western Tasmania from mid July through August however away from these regions it has been exceptionally dry with little tropical moisture coming down from the Indian ocean.

Despite the dry in April we said we DID NOT see an EL NINO developing this year despite the BOM having us on an EL NINO watch and by June the BOM also realised this by forecasting neutral for the rest of the year.

The question is will the current climate conditions change? The short to medium term answer is no, there are signs the cool patch in the Indian ocean is finally moving away from Indonesia or is starting to dissipate with warmer water developing off the north coast of WA and with the Pacific doing us a favour and swinging round closer to a La Nina with recent cooling that will eventually allow for better moisture and better rainfall especially northern and eastern Australia by November and December. As it stands 3.4 NINO is at -0.6c below normal. Sustained easterly trade winds since early June has produced the cooling.

In the meantime we expect this dry pattern to continue with little moisture from the tropics with October to be a transitional month and by the time we move into late Spring and early Summer we expect wetter conditions. The atmosphere takes at least 3-4 weeks before it starts responding to the oceans.

So all in all 2017 will be a dry year for large parts of Australia but there are some better signs as we move deep into Spring and towards December and the new year as we predict average to above average rainfall for northern and eastern Australia.

The cyclone/monsoon season my also be an active one across northern Australia due to the oceans and atmospheric conditions.

Image - showing of a potential La Nina to develop over the coming months.

- John's Weather Channel - https://www.facebook.com/JohnsWeatherChannelJwc/