A warm air mass drifting over WA during the next few days will deliver Perth its warmest weekend in seven months.

A near-stationary low pressure trough along Australia's west coast will help draw warm inland air towards Perth this weekend.

The city is forecast to reach 29 degrees on Saturday and a summer-like 34 degrees on Sunday. The city hasn't had both weekend days at or above 29 degrees since March.

Sunday could also be Perth's warmest day this early in spring for six years. In 2014, the mercury reached 35.4 degrees on October 15 and 34.2 degrees on September 20.

The city's warmest October day on record was 37.3 degrees on the 12th day of the month in 1933.