Weather in Margaret River

Summer can arrive slowly and in cool years it's not really good beach and swimming weather until around Christmas.
The average December day hovers around a maximum 25C, but evenings can be chilly, down around 12C.
There is a rule among locals that it's best to have a jumper in the car at all times.
January and February are the hottest months with the highest temperatures up toward the 40C mark, but seldom higher.
You can expect only five days in January and February to be over 35C, and about 16 when the maximum exceeds 30C.

Often characterised as 'Mediterranean' (especially in tourism circles), the climate of Margaret River passes through four distinct seasons.
One of the cooler parts of the state (given its southerly latitude and exposure to the winds of the Indian Ocean), summer conditions are nowhere near as ferocious as they are further north.
Between December and February, average daily temperatures range between 27C and 29C. Hot northeasterlies from the centre of the continent can also make this the windiest time of the year.

Note:
Margaret River lays a bit more inland, we are close to the coast so it will be cooler there.