Western inland WA is expected to be the hottest part of Australia this Saturday, as temperatures are expected to soar to the high 30s for the southwest corner, and into the low 40s for the northwest corner.

A surface trough extending down WA's west coast to north of Albany, combined with plentiful sunshine has allowed temperatures to rise as much as 7-10°C above the March average through the last few days.

Image: Much of inland western WA will heat up well above average. Source: Weatherzone 

Perth hasn’t been spared from the late season heat, with inland parts of the city exceeding 37°C each day since Wednesday. Perth Airport reached 39.1°C, 39.5°C and 37.3°C on Wednesday, Thursday and Friday respectively. On the same days, Pearce in the city’s outer northeast, reached temperatures of 39.2°C, 40.3°C and 39.6°C. Further north and again on the same days, Morawa, nearly 150km east-southeast of Geraldton, reached 38.9°C, 38.8°C and 40.1°C.

Image: Heatwave severity forecast for the period from Thursday 19th to Saturday 21st. Source: Weatherzone 

The lingering trough will start to edge further east on Saturday ahead of a cold front approaching the southwest coast, though there is at least one more day of summerlike heat expected across inland western WA, with a low intensity heatwave forecast across the region. Away from the southwest coast, temperatures will reach into the mid to high 30s once more. Temperatures across the Gascoyne and western Pilbara will likely be even hotter, cracking into the 40s for many areas.

From Sunday a cold front should bring some welcome relief for the southwest, though hot days may continue for the northwest until mid-next week ahead of the approach of Tropical Cyclone Narelle. The approach of Narelle will bring increased latent energy over northern parts of WA early to mid-next week. This should lead to spike in temperatures across the Pilbara from Tuesday.

Image: Perth Airport, along with much of southwest WA will become cooler from Sunday. Source: Weatherzone