A trough will develop about the west coast of WA over the next few days, resulting in a hot airmass being directed towards the coast.

At this stage, the airmass will be at its hottest over Perth on Tuesday, with the mercury expected to nudge above the 40 degree mark in some eastrn suburbs. The Fremantle Doctor will provide some relief from early afternoon in western parts of the city as winds swing in from the southwest.

Image: Forecast 2-metre temperature over the Perth area on Tuesday at 2pm AWST according to the Sat 12z run of ECMWF.

Gusty winds associated with the trough will reduce nocturnal cooling on Monday and Tuesday night, with the mercury looking to be stuck in the mid-20’s until at least 10pm both nights.

The trough will gain moisture and the airmass will begin to cool from Wednesday 9th, resulting in less hot daytime temperature, although the humidity will increase.

Greater amounts of cloud cover and the threat of showers and storms, will also act to suppress nocturnal cooling each night from Wednesday to Friday.