Smoke alerts have been issued for several suburbs south of Mandurah.
Residents in North Dandalup, Preston Beach, Dawesville and Bouvard are included in the alert.
The smoke is due to a number of prescribed burns.
Motorists travelling along the South Western Highway between Del Park Road and Morrell Road may be impacted by smoke.
Other affected roads include Preston Beach Road North and Old Coast Road between White Hills Road and Tims Thickett Road.
The smoke is expected to clear over the coming days.

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