THE CLIMATE KELPIE BLOG: What are the Climatedogs up to in August

Posted by BCG on 1st August 2018

Our Climatedogs drive Australia’s climate in different ways at different times of the year. ENSO and Indy are currently both still neutral.

August is forecast to be drier than average across the eastern half of mainland Australia, with only Tasmania forecast to have higher than average rainfall for August (see image below). Daytime temperatures are likely to be warmer than average for all of Australia in August, and nights are likely to be warmer than average in most parts except far north Queensland and the south western corner of Western Australia.

BoM’s El Niño watch means that there is approximately 50 per cent or double the likelihood of an El Niño forming this year (Source: BoM).

Enso - El Niño Southern Oscillation Indy - Indian Ocean Dipole

 

Rainfall Roundup

So far, large areas of Australia are looking dry, with areas experiencing their lowest rainfall on record, but with no clear influence from the Climatedogs.

Figure 1. Rainfall deciles for July 2018.

Figure 2. Rainfall deciles for February to July 2018.

Rainfall Forecast

The BoM forecast for August is for conditions to remain dry for large parts of eastern Australia, with the west indicting average to slightly below average rainfall. Tasmania is bucking the trend, with an average to slightly above average forecast projected.

Temperature Roundup

Maximum temperatures have been above average across both the eastern and western cropping regions, while minimums have been mostly average, except for the slightly warmer northern region and the Victorian/Tasmanian region.

Figure 4. maximum temperature deciles for July 2018.

Figure 5. minimum temperature deciles for July 2018.

Temperature Forecast

BoM forecasts suggest the whole country will experience above average maximum temperatures from August to October, with August to be warmer than September.

Minimum temperatures are forecast to be average in northern Queensland, with the forecast for the rest of the country warmer than average.  The August forecast shows central/southern Australia will experience above average minimum temperatures, while in September the west will move closer to average.

Climate and Water Outlook Videos

The Bureau of Meteorology releases fortnightly outlook videos that cover all of this information.  The end of month video can be found below.

 

The Climatedogs in Detail

If you’re keen to know what each of our dogs is up to at the moment, look no further!  They’re all available here.

Enso is predicted to be neutral in August

Enso is neutral at the moment, but many models predict a late spring/summer forming event.

The BoM El Niño watch means that there is approximately 50% or double the chance of an El Niño event this year.

While models are varied on the month El Niño levels will be reached, El Niño conditions have had an impact on the wet season onset for northern Australia. BoM provide a great resource of northern Australia rainfall onset here.

You can see Enso here:  http://www.bom.gov.au/climate/enso/#tabs=Overview

 

Indy - Indian Ocean DipoleIndy is predicted to be neutral in August

Indy is neutral at the moment; however a positive Indian Ocean Dipole has been indicated by most of the international climate models to form in the coming months.

Positive Indy generally means below-average winter and spring rainfall across southern and central Australia.

You can see Indy here:  http://www.bom.gov.au/climate/enso/#tabs=Overview

 

Ridgy - Subtropical RidgeRidgy sitting higher than normal

After stubbornly hanging around just over South Australia, Ridgy has moved both eastwards and northwards, this can potentially allow frontal systems to move more freely through southern Australia. While Ridgy is sitting over NSW it is not conducive for rain in that region.

 

 

Sam - Southern Annular ModeSam moving erratically

During July, Sam moved through both positive and negative phases.  Models predict Sam will be in the negative phase for the first few weeks of August. This will hopefully mean more rain fronts are able to move across southern Australia.

 

Eastie - East-Coast Low Pressure System

Eastie was less active than usual

Eastie is a volatile dog and it’s hard to predict where he’ll pop up. Historically, June has been the month with the maximum frequency of East Coast Lows. It looks like Eastie is on vacation.

 

Mojo - Madden-Julian OscillationMojo is trending weaker

Mojo had a strong favourable burst in mid-July, but connections to the south were poor at that time. Mojo has reduced in intensity over the past week as it has been in the Western Pacific Ocean. When Mojo becomes weak or indiscernible it will have little influence on tropical rainfall patterns.

You can see Mojo here:  http://www.bom.gov.au/climate/mjo/#tabs=MJO-phase