Sydney's summer tempered by coast breezes as the west nudges records
Sydney has most likely notched one of its five warmest summers, while some western suburbs will probably fall just shy of their hottest season on record.
With a final day's data of February to be added, Sydney's Observatory Hill is likely to have posted its fifth-warmest summer by mean and maximum temperatures in records that go back to 1859, Weatherzone said.
The coast was the place to be this summer, with sea breezes providing reliable relief for Sydney.
Photo: Glenn CampbellThe mean temperature for the site will probably be 23.8 degrees, 1.8 degrees above the norm, but a full degree short of the "stand-out" record set for the summer of 2016-17, Brett Dutschke, senior meteorologist for Weatherzone, said.
Daytime temperatures averaged 27.7 degrees - also about a degree shy of last year's record - but 2 degrees warmer than what's typical for summer in Sydney. Night-time temperatures averaged just under 20 degrees, according to Weatherzone's analysis of data from the Bureau of Meteorology.
Sea breezes proved a reliable moderator for the coastal strip, taking the edge off a number of heatwaves.
"The high that had been over the Tasman Sea for much of the season - as it typically is - was just near enough to the coast so that sea breezes could be the dominant feature for the city and the beaches," Mr Dutschke said.
Indeed, inland suburbs such as Richmond and Penrith sweltered through one of their hottest summers.
Excluding Wednesday's final reading for February, Richmond will have had 36 days above 35-degrees, beating last year's previous record of 35 such days.
During the past 80 years at the site, the average number of days of 35 degrees or warmer was just 22, Mr Dutschke said.
With autumn beginning on Thursday, the next chance for a 35-degree day in Richmond is probably this Sunday, he said.
Average summer maximum temperatures in Richmond will probably fall just short of the 32.93-degree record for 1939-40, a summer notorious for huge bushfires across south-eastern Australia.
A late summer deluge in Sydney - the falls of Sunday into Monday of 69.4 millimetres were the most in a 24-hour period in a year - helped lift Observatory Hill's total for the season to 197 millimetres. That's about two-thirds of the seasonal norm, and the driest summer at that site in four years, Mr Dutschke said.
That rain, part of widespread falls that included flooding in Canberra, will most likely have reduced bushfire risks significantly.
The NSW Rural Fire Service said there have been 17,946 firefighter deployments during the fire season so far.
Autumn outlook
A weak La Nina climate pattern in the Pacific barely impacted on Australia's summer rainfall, the bureau said.
That system - marked by stronger than normal easterly winds in the tropical Pacific - is breaking down, a process that has brought drier-than-average conditions to Australian autumns in the past, the bureau said in a seasonal outlook released on Wednesday.
The March-May period is likely to be particularly dry in central Australia, with the odds favouring closer-to-average rainfall along the east coast.
"For Sydney, autumn is likely to trend to being wetter than average," Mr Dutschke said. "The season is also likely to be near or slightly cooler than average to start but trend to warmer than average."
Australia-wide, odds favour an autumn that is warmer than average for most regions, particularly Tasmania, Victoria and the Northern Territory, the bureau said.
Weatherzone is owned by Fairfax Media, publisher of this website.
Peter Hannam is Environment Editor at The Sydney Morning Herald. He covers broad environmental issues ranging from climate change to renewable energy for Fairfax Media.
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