A smoke alert has been issued for North Bannister, Serpentine, Keysbrook, Mandurah and Rockingham.
The smoke is due to a prescribed burn north-east of Dwellingup.
"People travelling along Albany Highway and surrounding roads in the area are advised smoke may impact visibility," a Department of Fire and Emergency Services alert read.
"Please be aware of crews working in the area and drive to the conditions."
The smoke is expected to clear overnight.
Affected residents are advised to shut doors and windows and turn off airconditioners.
If driving through the area, turn on headlights and drive slowly.

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