Since its direct exposure to the Tasman Sea, Westland Tai Poutini often faces western winds that can bring heavy rainfall at any time of the year. Its annual precipitation is estimated to range between 5000 and 8000 mm. The local weather is known for rapid changes in a short amount of time.
In lowland areas, daily average temperatures from November to April vary between 12°C and 16°C, while daily average temperatures in winter months range from 7°C to 10°C.