Sydney will be cooler today than yesterday.  A good 20 degrees cooler.  That is likely a change many will welcome after yesterday.

Friday was the hottest it has ever been in Sydney.  Well, at least the hottest it has ever been since they started keeping records over 150 years ago.

On Friday the temperature smashed the previous hottest recorded temperature peaking at 45.8 degrees Celsius (114.4 Fahrenheit). The old record, of 45.3 C (113.5 Fahrenheit), was set in January 1939.

“It’s a historic day for Sydney,” Dick Whitaker, meteorologist with The Weather Channel.  “We haven’t seen a day like this in Sydney’s recorded history.”

It is the latest record to fall as Australia swelters under a heat wave that has affected 70 percent of the vast country and created what experts have called a “dome of heat” over the nation’s outback centre.

The Bureau of Meteorology said the heat wave had been affecting large parts of Australia since late 2012, and the Sydney record set at Observatory Hill — where the temperature has been measured since 1859 — was just the latest.

“The record setting temperatures were not limited to Sydney, with records being set along the coast,” the bureau said.

“The highest temperature recorded in the Greater Sydney area was 46.5 C (115.7 F) at Penrith.”

The scorching heat follows an extended period of exceptionally widespread hot weather for Australia in which the nation experienced its hottest day on record on Jan. 7 with the average maximum temperature hitting 40.33 C  (104.5 F).

The extreme weather, which has exacerbated fires, last week also saw the government’s weather bureau upgrade its temperature scale by introducing new colors to cover projected forecast highs.

At one point last week, central Australia was shown with a purple area on the bureau’s forecast map, a new colour code suggesting temperatures were set to soar above 50 degrees (122 Fahrenheit).

Australia’s all-time record temperature is 50.7 C (123.2 F), set in January 1960 at Oodnadatta in South Australia.

Firefighters are battling blazes in New South Wales and Victoria, almost two weeks after a dangerous fire in the southern island state of Tasmania razed more than 100 homes.

The unprecedented heat wave prompted the government’s Climate Commission to issue a new report on the weather event last weekend.

It said climate change had contributed to making the extreme heat conditions and fires even worse.

“The length, extent and severity of the current heat wave are unprecedented in the measurement record,” the report Off the Charts: Extreme Australian Summer Heat noted.

“Although Australia has always had heat waves, hot days and bush fires, climate change is increasing the risk of more frequent and longer heat waves and more extreme hot days, as well as exacerbating bush fire conditions.”

-WeatherWatch.co.nz and The Weather Channel