THE CLIMATE KELPIE BLOG: What’s predicted in November?

Posted by BCG on 8th November 2019

The very strong positive Indian Ocean Dipole (IOD) is forecast to extend well into December which is several weeks later than usual. The negative phase of the Southern Annular Mode (SAM) is also likely to continue, contributing to the hot and dry conditions forecast for Eastern Australia. However, both the positive IOD and negative SAM are likely to break down over summer. The northern wet season is looking like it will arrive later than previous years as the movement of the monsoon trough down to the Southern Hemisphere is experiencing delays. The outlook therefore for the remainder of 2019 and into early 2020 is for likely hotter and drier conditions for most of Australia with “Below Average” rainfall.

Rainfall Roundup

In October, large parts of Australia continued to remain very dry (Fig. 1). Pockets of QLD, NT and WA were fortunate enough to receive “Above Average” rainfall for October. For example, parts of QLD received more than 30mm in late October. The generally dry conditions of October have contributed greatly to the “Below Average” to “Very Much Below Average” rainfall conditions across Australia for the last 3 months with the Murray Darling Basin, and parts of QLD, SA and WA recording the “Lowest on Record” (Fig. 2).

Figure 1. Rainfall deciles for October 2019.
Figure 2. Rainfall deciles for August to October 2019.

Rainfall Forecast

The BoM’s ACCESS model suggests that for November and December most of Australia is likely to receive “Below Average” rainfall, particularly in the eastern states, except for western Tasmania which is forecast to receive “Above Average” rainfall (Fig. 3). However, during January there are indications that the dry signals are likely to ease in the new year.

The outlook for the northern rainfall season suggests that the first rains are likely to arrive later than usual. A delay in the tropical cyclone season in Australia is also expected and fewer than average cyclones are forecast to fall in our region.

At this time of year accuracy for the three-month forecast is moderate, except for parts of NSW, SA, WA and much of the NT which have low accuracy at this time of year (Fig. 3).

Figure 3. Australian outlook for November to January 2019.

Temperature Roundup

In October, maximum temperatures were “Very Much Above Average”, across much of Australia (Fig. 4). The burst of heat on the 24th of October brought temperatures more than 12°C “Above Average” to parts of the south east of Australia.

Minimum temperatures were “Below Average” across northern Australia and Tasmania, “Average” along the east coast of Australia and “Above Average” across large parts of WA, SA and areas of NSW and QLD (Fig. 5).

Figure 4. Maximum temperature deciles for October 2019.
Figure 5. Minimum temperature deciles for October 2019.

Temperature Forecast

The BoM’s ACCESS model forecast suggests “Above Average” maximum temperatures are likely across most of Australia over the next three months (Fig. 6). Minimum temperatures are also likely to be “Above Average” for large parts of the country except for Vic, Tas and southern NSW and SA which look likely to be “Below Average” (Fig. 7).

At this time of year accuracy for the three-month forecast is moderate to high for the maximum temperatures (except for a pocket in the NT which has low accuracy). Accuracy is moderate across most of Australia for the minimum temperatures (except for parts of QLD, NT and WA which have low accuracy).  

Figure 6. November to January maximum temperature outlook.
Figure 7. November to January minimum temperature outlook.

Climate and Water Outlook Videos

The Bureau of Meteorology releases regular outlook videos, covering all this information. Watch the most recent video below.

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