South-eastern Australia is in for another burst of summer later this week, with most of coastal NSW, including Sydney, facing severe heatwave conditions.
A broad trough will direct heat from the Red Centre, pushing temperatures in western Sydney potentially close to, or exceeding, 40 degrees for five days in a row from Thursday.
Penrith - which this month posted 47.3 degrees, the hottest recorded in the Sydney Basin since 1939 - is forecast to bake during the spell.
Revised predictions by the Bureau of Meteorology indicate the region is likely to endure tops of 42 or 43 degrees on Friday, Saturday and Monday.
This week's heatwave "will be similar in length but not as intense" as the one at the start of January, Graeme Brittain, a forecaster at Weatherzone, said.
Sea breezes are tipped to spare eastern suburbs the worst of the heat, with temperatures expected to be capped at 30-32 degrees during the four days from Friday, the bureau said.
Still, should the onshore winds fail to kick in by midday or soon after on any of the days, the mercury in the CBD could spike as well, Mr Brittain said.
Temperatures will also soar in Adelaide and Melbourne as the continental heat slips southward.
The Australian Open could be in for a couple of punishing days for players and fans, with 38 and 39 degrees tipped for Melbourne on Thursday and Friday.
According to the bureau's heatwave service, most of eastern NSW and a part of eastern Victoria will be in for severe heatwave conditions by Friday.
A region between the ACT and the coast will be in for an extreme heatwave. (See updated chart below.)
Monday may also be hot for Sydney, with a cool change not expected at this stage until late in the day or into Tuesday, Mr Brittain said.
Mild overnight temperatures and rising humidity by Sunday will make it more difficult for some people to recover from the daytime heat.
There is also little rainfall forecast for the coming week, so fire risks are likely to be elevated along with the temperatures, particularly if winds pick up.
And while the beach may be the place to head during the sunny days this week, extra care might be needed because of rough conditions expected for Monday and Tuesday at least.
The bureau has issued a hazardous surf warning for the NSW coast for Tuesday, taking in beaches all the way from Byron in the north to the Batemans and Eden coasts in the south.
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