Record heatwave matched and more to come - Sydney Morning Herald

Not all beach and skittle as long heat sets in.

Melbourne's exceptionally hot March has matched a long-standing record while the same stationary weather pattern is also putting Sydney on track for a lengthy spell of warm conditions.

Temperatures in the Victorian capital touched 30 degrees late Sunday morning, marking seven consecutive days of 30 degrees or warmer weather.

Before this month, the city had only achieved such a long hot spell three times in March in 156 years of official records, said Brett Dutschke, senior meteorologist at Weatherzone.

“It's quite likely that the following three days will be in the mid-30s,” Dr Dutschke said, which would smash the previous record length – eight days – for any month of the year.

Further north, Sydney today reached 27 degrees, marking the eighth straight day of 25 degrees or warmer. “It looks like it's going for 14 days” of such weather, Dr Dutschke said.

The Harbour City has only recorded such a stint once before for March – in 2006 – although it has twice before had 15 such days in a row. “There's a chance it could go to 15,” he said.

Australia posted its hottest summer on record for the previous three months as measured by average maximum or mean temperatures, and much of southern Australia has seen the above-normal heat continue.

The cause for the current extra warmth is a so-called blocking high pressure system over the Tasman Sea, which is directing hot northerly winds over the south-east of the continent.

“The cool changes have also been so weak, they've hardly penetrated north of Tasmania,” he said.

Humidity is also higher than usual “over almost the whole country”, he said, adding to the discomfort, particularly for those in Melbourne.

The southern city is expecting maximums of 34, 36, and 37 degrees, respectively, over the first three days of the week, with a cool change only arriving either late on Wednesday or early Thursday. Minimums won't drop below 21 until Friday, the weather bureau predicts.

Melbourne's long-term average daily temperatures in March range from a minimum of 13.2 and a maximum of 23.9 degrees, Dr Dutschke said.

Sydney's minimum is not expected to fall below 19 for the whole week ahead, with maximums of 27 degrees rising to 30 degrees by next Saturday, the weather bureau forecasts. That compares with a normal range of between 17.6 and 24.7 degrees for March.

Tropical cyclone Sandra, meanwhile, remains well off the nation's north-east coast, and “it is highly unlikely it will have a direct impact” on Australia, Dr Dutschke said.

Weatherzone is owned by Fairfax Media, publisher of this website.