Weather on the Islands

The ideal time to visit the Mackerel Islands is in the Pilbara winter season, from late March through to early November. This is when the weather is cooler and drier than in the summer months, with average maximum temperatures ranging between 25° and 33° Celsius, and average minimum temperatures ranging between 15° and 24° Celsius.

Visitors from southern parts of Australia during winter relish the warm, dry sunny weather during Pilbara winters. The Mackerel Islands offers a unique island escape where people can disconnect from life’s bustle and reconnect with nature, friends and family to soak up magnificent vistas of sparkling sunshine, ocean blues, and untouched terrain during this time.

The town of Onslow, from where the islands are accessible, is classified as sub-tropical and semi-arid. During the summer months in November through to March is popular for locals and road travellers seeking a dose of coastal revitalisation and respite from summer’s heat. Average minimum temperatures range from 18° to 25° Celsius, while average maxima range from 30° to 38° Celsius.


Most of the region’s rainfall occurs during the summer months, with annual precipitation averaging around 430mm, or 17 inches (430 litres per square metre). We are prone to some pretty impressive storms and cyclones occasionally!


The wind during winter months comes predominantly from the SE and eases during the morning. It differs from the wind in the southern part of Western Australia, where an afternoon sea breeze is experienced. There is no need to get up early and rush out in your boat, as the day generally keeps on getting better!

There is also minimal swell in the area, meaning once the wind decreases so too does the sea state. It is not uncommon to experience afternoon ‘glass-offs’ – perfect conditions for stand-up-paddling and other marine activities.

Fun Weather Fact!

Q: Imagine burrowing down through the centre of the earth from Onslow, Western Australia. Where would you end up?

A: The climate station in San Juan, Puerto Rico, USA, where the climate is tropical monsoonal.

(Source: Onslow Climatemps)