Cool
Average highs are around 9°C, so pack for cooler days.
Weather Guide
Stewart Island, New Zealand Average Monthly Weather
Weather score19Poor annual avg
Best months: February, December, January
Across the year, average daytime temperatures are around 13°C, sunshine averages 4h per day, and rainfall totals about 1223mm. Sea temperatures average 13°C across the year.
Annual weather
Annual averages
Temp
13°C
Rain
1223mm
Annual total
Sun
4h
Sea
13°C
Weather score
19
Poor avg
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
SwimSwim
Weather scoreWeather score
Trip feel
Showers
Rainfall averages 103mm, so some wet days are possible.
Limited sun
Sunshine averages 2.3h per day, so this is not one of the brighter months.
Cool sea
Sea temperatures average 11°C, so the water can feel cool.
Map
Weather map
Compare Stewart Island, New Zealand with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
July9°C average high
July has some of the coolest average daytime highs of the year, so pack for fresher conditions.
Warmest monthsJanuary to March and December
This stretch sets the upper range for average daytime heat.
Rain
July103mm average rain
July sits near Stewart Island's yearly rainfall average, so rain is a normal planning factor rather than an outlier.
Driest monthsFebruary to March and June to December
This is the drier part of the year, when outdoor plans usually need less weather flexibility.
Sun
July2.3 hours average sun
July is one of Stewart Island's cloudier months, so sunshine-led plans are less reliable.
Brightest monthsJanuary to February and October to December
This stretch has the strongest sunshine in the monthly averages.
Sea temperature
July11°C average sea
July is one of the coolest sea months, so the water may feel fresher than in peak months.
Warmest seaJanuary to April and December
Sea temperatures are usually near 14°C in this stretch, so swimming comfort is at its strongest.
Weather score
July14 weather score
July is one of the weakest weather-score months, when the overall mix is less favourable than the rest of the year.
Best weather monthsJanuary to March and November to December
These months have the strongest weather score in the monthly averages.