This will be the hottest first week in December on record if predicted temperatures prove correct.

Bureau of Meteorology spokesman Neil Bennett said Perth had sweltered through three consecutive days of more than 35C, with December 2 hitting 35.6C, December 3 reaching a whopping 41.6C, and Wednesday reaching 37.6C.

Perth is set to swelter through the rest of the week as temperature records are broken. Credit:Jessica Shapiro

Mr Bennett said the mean maximum temperature for the first seven days in December was likely to be about 36C, based on latest observations and forecasts.

"This will be the hottest first week in December on record if those forecasts are correct," he said. "The previous hottest first week in December was 35C in 1931."