Wellington Temperature Market Guide

Wellington International Airport (NZWN) serves as the primary weather observation station for New Zealand's capital. Located on the Rongotai isthmus between Evans Bay and Lyall Bay, the airport sits at just 41 feet elevation in one of the most wind-exposed locations in the country.

The station's position near the Cook Strait - the body of water separating New Zealand's North and South Islands - means it experiences persistent wind and rapidly changing conditions. Temperature observations are reported in Celsius and follow World Meteorological Organization standards.

Wellington's latitude of 41°S places it in the path of frequent frontal systems moving eastward across the Tasman Sea.

Wellington has a temperate maritime climate (Koppen: Cfb) characterized by mild temperatures year-round, frequent wind, and regular rainfall. The city rarely experiences temperature extremes due to the moderating influence of the surrounding ocean.

Summer (December-February) brings average highs around 20°C (68°F), while winter (June-August) sees highs around 11°C (52°F). Temperatures above 25°C (77°F) are uncommon, and frost is rare at the airport location.

The persistent westerly wind flow means weather changes rapidly, with four seasons in one day being a common local saying.

Summer (December - February): Mild and pleasant with highs around 20°C (68°F). Strong winds can suppress temperatures. Sea breezes provide natural air conditioning. Extended daylight hours (up to 16 hours).

Autumn (March - May): Gradually cooling with increasing rainfall. Temperatures drop from high teens to low teens Celsius. More frequent frontal passages. First significant cold snaps possible in May.

Winter (June - August): Cool but mild for the latitude with highs around 11°C (52°F). Frost rare at airport level but common in surrounding hills. Shortest days with only 9 hours of daylight.

Spring (September - November): Variable and windy. Temperatures slowly climb but can drop sharply with southerly changes. Notorious for unpredictable conditions.

Wind is the dominant factor in Wellington's climate. Strong northwesterly winds ahead of fronts bring warmer temperatures, while southerly changes behind fronts can drop temperatures 10°C or more within hours.

The Cook Strait funneling effect amplifies wind speeds and can create localized cooling. When gale-force winds are forecast, expect temperatures to struggle to reach predicted highs.

Remember the Southern Hemisphere seasons are reversed - Wellington's summer runs December through February. The warmest months are January and February.

Check for southerly changes in forecast models. A cold front passage can dramatically alter the temperature outlook within a 24-hour period. The timing of frontal passages is critical.

MetService New Zealand forecasts are the most reliable local source. Their airport-specific forecasts account for the unique microclimate of NZWN.

Wellington temperature markets resolve using the official daily maximum temperature recorded at NZWN as published by MetService New Zealand. Temperatures are recorded in Celsius.

The observation day in New Zealand runs from 9 AM to 9 AM local time (NZST/NZDT), which differs from the midnight-to-midnight convention used in the United States.

View Wellington Weather at MetService →

Wind-Driven Variability: Wellington's extreme windiness makes temperature forecasting challenging. Strong winds increase evaporative cooling and can prevent expected highs from being reached.

Rapid Weather Changes: Frontal systems cross the region frequently, bringing rapid temperature changes that can invalidate forecasts made even 24 hours prior.

Cook Strait Effects: The narrow strait between the North and South Islands creates complex local wind patterns and temperature gradients.

Observation Day Definition: The 9 AM to 9 AM observation period differs from US conventions, which can cause confusion for traders accustomed to midnight-to-midnight readings.

Marine Layer: Low cloud and fog from the ocean can persist, limiting daytime heating especially in summer.

Record High: 31.1°C (88°F) recorded on January 30, 2019.

Record Low: -3.9°C (25°F) recorded on July 20, 1944.

Historical Note: Wellington's maritime position prevents extreme temperatures. The city has never officially recorded a temperature above 32°C (90°F) or below -4°C (25°F) at the airport station.