Weather in Port Moresby in September 2025
Average weather
Average temperature in Port Moresby in September
The expected average maximum temperature in September is +29°C with a maximum of +31°C and a minimum of +19°C.
The average maximum temperature goes up 25% by the end of the month, compared with the beginning of the month, from +28°C to +31°C.
Is Port Moresby warm or cold in September?
Port Moresby is typically warm in September.
Maximum temperatures go up compared to the previous month from +28°C to +28°C. The minimum temperature also goes up from +23°C to +23°C.
It’s generally warm, but pack a long-sleeve shirt for evenings.
Take a look at how September is compared to other months in Port Moresby:
Climate in Port Moresby in September
| August | September | October | ||||
|---|---|---|---|---|---|---|
| Avg. temperature | ||||||
| +28°C | +28°C | +29°C | ||||
| Min. temperature | ||||||
| +17°C | +18°C | +19°C | ||||
| Max. temperature | ||||||
| +31°C | +31°C | +32°C | ||||
| Rainfall | ||||||
| 31 mm | 42 mm | 67 mm | ||||
| Wind | ||||||
| 3 m/s | 3 m/s | 2 m/s | ||||
| Humidity | ||||||
| 80% | 80% | 81% | ||||
| Air pressure | ||||||
| 1011 HPa | 1010 HPa | 1009 HPa | ||||
| Sunny days | ||||||
| 2 | 2 | 1 | ||||
| Cloudy days | ||||||
| 17 | 13 | 11 | ||||
| Rainy days | ||||||
| 12 | 14 | 18 | ||||
| Snowy days | ||||||
| 0 | 0 | 0 | ||||
September weather is still as good as in August. The temperature levels stay the same in the area of +28°C for average maximum temperature during the day. Prepare for more rain. Average rainfall goes from 31 mm to 42 mm. Humidity levels don’t change as the month goes on, averaging around 80%. The average wind speed doesn’t change much during September, staying around 3 m/s. The amount of sunny days stay about the same, averaging 2 sunny days during the month.
Next month (October) brings a further decline in the weather.
Wind
The average wind speed is 5 m/s getting up to 8 m/s which is a medium breeze. You can feel it, especially getting out of the water.
The average wind speed in Port Moresby is gradually increasing during September, going from 5 m/s to 6 m/s over the course of the month.
Rain
How was the weather last September in Port Moresby?
Climate Change over Years
The climate in Port Moresby in September has not changed much over the last 43 years.
The average temperature was the lowest in 1982 (+28°C) and the highest in 2024 (+30°C). The driest year was 1997 with only 892 mm of rainfall, and the wettest year was 2006 with 1873 mm.
FAQ
Is September a good time to visit Port Moresby?
Can you sunbathe in Port Moresby in September?
Is Port Moresby rainy in September?
Is it sunny in Port Moresby in September?
Other cities in Papua New Guinea
Monthly weather in Port Moresby
Source of the data
For this page, we’ve looked at the typical weather in Port Moresby, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.
