Sydney broke its previous records for warmth in May, with maximums almost 4 degrees above average. More unseasonably warm temperatures are likely in the coming week.
A typical day in the Harbour City last month had a top of 23.2 degrees, well above the long-run average of 19.4 degrees, and a good half a degree above the previous record set in 1958.
The city’s gauges collected less than a quarter of the usual rain for the month, at just 27.4 millimetres, making it the driest May in six years.
Fewer clouds, though, also meant more sun. Each May day this year had 7.5 hours of sunshine on average, or about 90 minutes more than usual, the Bureau of Meteorology said, citing data from Sydney Airport.
Sydney also posted it hottest autumn in the 155 years of records, with average maximums of 24.5 degrees beating the previous high of 24.1 degrees set in 2006. Mean temperatures also edged out 1958 as the previous highest.
The city has now had its warmest winter, spring and now autumn on record over the past 12 months. Summer was less extreme but also the driest since 1986-87, a trend that continued with autumn rainfall just two-thirds of the long-run average.
As might be expected with that series, Sydney’s past 12 months have been the city’s warmest on record, eclipsing the previous run to March 2006, according to Acacia Pepler, a climatologist at the bureau.
The bureau’s three-month outlook, released last week, indicate Sydney is likely to have a warmer and drier than average winter. An El Nino forming in the Pacific may also mean such conditions extend further into the year, increasing the chance of droughts and bushfires.
Autumn was remarkable for its long periods of warm weather, a trend that will continue this week. Monday’s maximum reached 22.3 degrees, the 29th consecutive day above 20 degrees, and easily more than the previous record of 19 set in 1978 and 2007.
On the present forecast, the city may extend that record run to 34 days, with the series to end next Sunday.
A dominant high-pressure system over the Tasman will direct a few showers Sydney’s way on most days of the coming week, but top temperatures should continue to reach 19-21 degrees. The June average top is 16.9 degrees.
Statewide, all of NSW posted above-average temperatures for autumn, with rainfall slightly above the norm.
Nationally, May was the fifth-warmest on record, with area-averaged maximums 1.57 degrees above average. Mean temperatures were the third-warmest on record, with an anomaly of 1.62 degrees.
The autumn as a whole was Australia’s third-warmest on record for both minimum and mean temperatures, and the sixth warmest for maximums.
Climatologists say Australia has warmed about 0.9 degrees over the past century, a clear signal of climate change. That added warmth makes it more likely heat records will fall and less likely cold ones will.