Swimming in Stewart Island in september 2025: Average sea temperature in september and tide times in september 2025
Average sea temperature in Stewart Island in september 2025.
In september, according to seasonal norms, the sea temperature in Stewart Island is:
Minimum: 51°F
Average: 52°F
Maximum: 54°F
Other useful seasonal weather averages in september:
- Outside temperature: 43°F to 54°F
- Most common weather: "Moderate rain at times"
- The wind blows at 1.9mph
- It rains a total of 5.9in, over 11 day(s).
Should we swim in Stewart Island in september?
No... The water temperature in Stewart Island in september is freezing
You won't be able to swim in Stewart Island in september! The water temperature is freezing, reaching as low as 51°F (and only 54°F at best)! Our advice: if you are going to Stewart Island this month, plan to sightsee and forget the beach!
Note also that in september, the climate is bad with an average outside temperature of 48°F, 5.9in of precipitation (over 11 days) and 87.21 % humidity.
Water and normal seasonal temperatures in Stewart Island in september
| September | |||
| Average sea temperature | 52°F | ||
| Minimum sea temperature | 51°F | ||
| Maximum sea temperature | 54°F | ||
| Average outside temperature | 49°F | ||
| Maximum outside temperature | 54°F | ||
| Minimum outside temperature | 43°F | ||
| Wind speed | 14.3mph | ||
| Wind temperature | 38°F | ||
| Precipitation | 5.9in | ||
| Number of days of rain | 11 jour(s) (35%) | ||
| Humidity | 88% | ||
| Visibility in kilometers | 9.03km | ||
| Cloud cover | 50% | ||
| Our opinion | freezing swimming |
Chart of the tides in september 2025
Tide times in september 2025 in Stewart Island
Swim elsewhere in New Zealand in september
| City | Average T° | Min. T° | Max. T° | Our opinion | Auckland in september | 60°F | 61°F | cold swimming | Christchurch in september | 51°F | 53°F | freezing swimming | Dunedin in september | 49°F | 51°F | freezing swimming | Wellington in september | 56°F | 58°F | freezing swimming | Tauranga in september | 60°F | 62°F | cold swimming | Akaroa in september | 51°F | 53°F | freezing swimming | Cathedral Cove in september | 60°F | 62°F | cold swimming | Invercargill in september | 52°F | 54°F | freezing swimming | Napier in september | 57°F | 60°F | freezing swimming | Nelson in september | 56°F | 58°F | freezing swimming | Waiheke Island in september | 60°F | 62°F | cold swimming | Blenheim in september | 56°F | 58°F | freezing swimming | Greymouth in september | 55°F | 57°F | freezing swimming | New Plymouth in september | 58°F | 59°F | freezing swimming | Picton in september | 56°F | 58°F | freezing swimming | Timaru in september | 51°F | 53°F | freezing swimming |