Perth reached 40.3°C this Thursday, the first time the WA capital has topped 40°C in autumn since March 12, 2012.

Other suburbs and areas on the city fringe were hotter, with maximums of:

• 41.5°C at Perth Airport (an 18-year autumn high)
• 42.1°C at Millendon in the Swan Valley, about 30km northeast of the Perth CBD
• 42.5°C at Pearce RAAF Base on the city's northern outskirts (another 18-year autumn high)

The Fremantle Doctor kicked in during the afternoon, but not with much gusto.

While Rottnest Island shed more than eight degrees from its maximum of 37.7°C at 1:17 pm to 29.6°C by 4pm, the city’s coastal fringe only cooled down by 2-3 degrees over the same period, with minimal effect on the mercury further east.

The unseasonable heat was dragged over the city by easterly to northeasterly winds circulating around the high pressure system centred over the eastern part of the Great Australian Bight.

Image: Synoptic chart for Thursday, March 6, 2025.

When Perth last topped 40 back in 2012, there were actually two days straight of scorching temps, one of which reached 41.1°C.

Locals will be pleased to know that there will be no repeat of that this time around, with top temps dropping back to a degree or two either side of the 30-degree mark for the next week or so as the wind slowly shifts to a southeasterly aspect.