BOM spring review reveals warm weather and average rainfall — with another hot summer on the way
The nation has just experienced the ninth-warmest spring on record, according to the Bureau of Meteorology, and above-average temperatures are expected to continue through summer.
Despite the season ending with heavy rainfall in some areas, the BOM’s freshly-released spring review does not offer much in the way of hope for those suffering through drought in the country’s east.
Senior Climatologist Dr Blair Trewin said average rainfall over New South Wales and southern Queensland had reduced the intensity of rainfall deficiencies, but it had not eliminated them.
- Ninth warmest spring on record nationally, with the north particularly hot
- Rain was patchy, Victoria and Tasmania largely below average
- Despite the torrential rain in some areas the drought got worse for others during spring
“There’s been some easing in some places, but much of inland eastern Australia is still showing significant rainfall deficiencies at a range of time scales,” Dr Trewin said.
“A lot of areas were running say, at third or fourth-driest on record for the year to date, as of the end of September.
“But they are now running at maybe sixth to tenth, certainly still significantly below average.
“In Victoria, the drought situation was probably worse during spring, particularly in the western half of the state.
“Despite some rain in November, we also have pretty notable long-term rainfall deficits in east Gippsland as well.”
He said for some areas of inland Queensland and a small area in the west of the Northern Territory, it was the warmest spring on record.
For spring, overall Victoria and Tasmania were dry, but the other states were more of a mix. (Supplied: Bureau of Meteorology )
Where and when did it rain?
Rainfall was “a bit of a mixed bag” over spring, according to Dr Trewin.
“It was the driest September on record nationally, but October and November rainfall returned to something closer to average,” he said.
“New South Wales and Queensland mostly came in very close to average for spring.
“Victoria and Tasmania were well below [average].
“Quite a lot of the outback, particularly in Western Australia, had a fairly wet spring but the south-west of Western Australia was dry.”
Impact of the late November storms
According to Dr Trewin, the part of coastal New South Wales that was impacted so severely by violent storms at the end of last month had received rain through much of spring.
“Sydney, for example, had some decent rain in September and October as well,” he said.
“Sydney had very heavy rain in that event in the last week of November, including 73 millimetres in an hour at one point.”
An hour’s drive south, the Illawarra region was also pelted with rain.
“The Illawarra is actually an area which has been really dry, since the middle of last year. So that was certainly welcomed for them.”
But Dr Trewin said the rainfall had been patchy.
“When you look at the totals for November for example, the central Sydney Observatory Hill had 176 millimetres for the month, but a lot of the other sites in metro Sydney were under 100 millimetres, which is still okay, but it’s significantly less.
“Then when you get up into the Hunter and you looking at 50, 60, 70 millimetres.”
Australian weather extremes for Spring 2018
|Hottest day||45.7C||Roebourne Aero, WA, on 18 November|
|Coldest day||-2.7C||Mt Hotham, Vic, on 2 September|
|Coldest night||-9.7C||Thredbo, NSW, on 24 September|
|Warmest night||32.2C||Marble Bar, WA, on 16 November|
|Wettest day||189mm||Beaumont, NSW, on 29th November|
Adapted from the BOM spring summary
Climate drivers ‘neutral’
Most of the climate drivers were neutral over spring, but Dr Trewin said sometimes a lack of a driver could be an influence in itself.
“The two ways you get relatively cooler conditions in the tropics are either there’s an early start to wet season, which hasn’t happened,” he said.
“Or alternatively, if you’re getting strong fronts coming across the southern part of the country which ends up pushing cooler air into northern Australia — and that hasn’t been happening either.”
There were above average temperatures for most of Australia, but particularly up north. (Supplied: Bureau of Meteorology )
Relief in sight?
The bad news is the latest outlook suggests conditions won’t be improving soon for much of the country.
There is a very high chance of temperatures above average this summer nation-wide and especially dry conditions for our north.