Parts of Western Australia will start their week with their hottest day in more than a year due to a suffocating combination of hot winds and temperatures soaring past 40 degrees.
A deepening trough over the Pilbara will move down the west coast tomorrow, with temperatures expected to hit a maximum of 35 degrees in Perth.
Most of the west coast will reach mid-to-high 30s, Geraldton 40 degrees, and inland Gascoyne and the Central West to exceed 40 degrees. 
Parts of Western Australia will start their week with their hottest day in over a year. (Weatherzone)
Weatherzone said for some parts of the state tomorrow will be the hottest day since last autumn.
The sweltering conditions have sparked moderate to extreme fire danger warnings across the state tomorrow, according to the Bureau of Meteorology. 
The Midwest Coast and Midwest Inland, including Geraldton, Northampton, Chapman Valley, Mingenew, Morawa, Perenjori and Three Springs, will be under an extreme warning.
Parts of the Kimberley, north interior, Pilbara, Burrup, Ashburton, Exmouth, west interior, Yalgar, Gascoyne, Lesueur, Yarra Yarra, Lockwood, Mortlock, Avon and Swan will be under a high warning while remaining parts of the state face moderate warnings.
South Goldfields is the only area to escape warnings tomorrow.
Moderate to severe fire danger warnings encompass most of the state tomorrow. (Emergency WA)
The trough is expected to generate moisture, which could cause thunderstorms across the western and southwestern parts of the state from as early as tomorrow.
But, as the week goes on, temperatures will fall. 
Perth will likely see storms beginning on Wednesday and Thursday, with the mercury expected to drop to 26 degrees by Saturday.
Storms will lash Geraldton and Gascoyne starting tomorrow and into Tuesday before conditions clear.
Temperatures will fall to 26 degrees in Geraldton and 34 degrees in Gascoyne by Saturday.