Climate Insights for Wairau Valley

The climate in Wairau Valley is temperate. The average annual temperature is 10°C and approximately 1476mm of precipitation falls per year. Wairau Valley receives a notable amount of rainfall throughout the year, including during its driest month. Wairau Valley is in the Southern Hemisphere. The seasons are reversed — summer runs from December to February, while winter falls between June and August. The summer months are: January, February, December. The coldest months are July, August, June, when temperatures can drop to 1°C.

Temperatures in Wairau Valley vary considerably across the year, with a 21°C difference between the coldest and warmest months. January is the warmest month, though highs remain moderate at 22°C with a mean of 16°C. July is the coolest month, with minimum temperatures around 1°C and an average of 5°C. On average, daily temperatures fluctuate by about 9°C between overnight lows and afternoon highs. The sharpest temperature change occurs between March and April, with a 3°C shift in average temperatures.

Wairau Valley is a fairly wet location, receiving approximately 1476mm of precipitation annually, which averages out to around 123mm per month. The wettest month is July, averaging 145mm of rainfall. December and May also tend to see above-average precipitation. The driest month is January, with just 95mm. That's 50mm less than July, the wettest month. Rainfall is relatively evenly distributed throughout the year, so there is no pronounced dry or wet season to plan around.

Wairau Valley is mildly breezy, with an average annual wind speed of 13km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is November, averaging 15km/h, though still comfortable for most outdoor activities. The calmest conditions occur in June, with average winds dropping to 10km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 5km/h gap between the calmest and windiest months. Wind tends to pick up during the summer months. The seasonal averages are 11km/h in winter, 15km/h in spring, 14km/h in summer, 12km/h in autumn.

It is currently autumn in Wairau Valley, which began on March 20, 2026. Wairau Valley is in the Southern Hemisphere, where the seasons are reversed — spring starts in September, summer in December, autumn in March, and winter in June. The warmest period peaks in January at around 22°C, while the coldest stretch bottoms out in July near 1°C. Winter is next, beginning on June 21, 2026 — 89 days from now.

The best time to visit Wairau Valley is during January, when the weather is most comfortable for travellers. During these months, average temperatures hover around 16°C with modest rainfall averaging 95mm per month. By contrast, July can be quite cold with temperatures dropping to 1°C. Despite being the best months overall, some rain is still likely — pack a waterproof layer and plan a mix of indoor and outdoor activities.

The table below shows monthly climate averages for Wairau Valley based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.