Last updated: August 31, 2025
Experience the tropical charm of Port Moresby, Papua New Guinea in September, where temperatures average around 25°C (78°F), with maximums reaching 30°C (87°F) and minimums dipping to 19°C (66°F). This month showcases a vibrant atmosphere characterized by 81 mm (3.2 in) of rainfall over 11 rainy days, contributing to the lush landscapes that define the region. With an average humidity level of 80%, visitors are greeted by a warm, tropical climate ideal for exploring the city's unique culture and natural beauty. Prepare for a blend of sun and occasional showers as you immerse yourself in this enchanting environment.
In September, Port Moresby experiences a subtle transition in temperatures as the city moves towards the end of the dry season. With a minimum of 19°C (66°F), the nights are pleasantly cool, while the average temperature hovers around 25°C (78°F), providing a comfortable backdrop for daily activities. The daytime warms up to a maximum of 30°C (87°F), consistent with the patterns observed in the preceding months. This slight dip in the minimum temperature from previous months marks a shift toward the cooler end of the spectrum, setting the stage for an inviting climate as the city prepares for the upcoming wet season. Overall, September is characterized by mild and stable weather, making it an ideal time for outdoor adventures and exploring Port Moresby’s vibrant culture.
In September, Port Moresby experiences a noticeable uptick in precipitation, receiving 81 mm (3.2 in) of rain over 11 days. This marks a gradual increase from the drier months of July and August, which saw the lowest totals at 45 mm (1.8 in) and 58 mm (2.3 in) respectively. As the city transitions into the more humid months of October and November, September sets the stage for the wetter season ahead, with rainfall beginning to pick up again after a relatively dry mid-year. This trend emphasizes the dynamic tropical climate of Papua New Guinea, where rainfall is a natural rhythm of life, shaping both the environment and daily activities.
In September, Port Moresby experiences a notable dip in humidity, dropping to 80%, the lowest level since May. This decline marks a shift from the high humidity levels that characterized the preceding months, as it gradually decreases from a peak of 88% in May and June. As the city transitions into early spring, the humidity starts to stabilize, remaining relatively consistent through the subsequent months at around 81% to 83%. This slight reprieve in September brings a refreshing change, offering residents and visitors a brief respite from the typically humid tropical climate. Overall, the trends suggest a seasonal pattern, where the humidity gradually rises through the first half of the year, peaking mid-year, before tapering off as the year progresses.
In September, Port Moresby, Papua New Guinea, experiences an extreme UV Index of 15, consistent with the trend seen throughout the previous months. This high UV rating indicates a steady risk of harm from unprotected sun exposure, maintaining a brief burn time of just 10 minutes. As the year progresses, the city generally showcases a strong reliance on sun safety measures, with UV Index values remaining particularly high from January through November. In fact, the levels fluctuate only slightly, reflecting a persistent need for vigilance against UV radiation year-round. Protect yourself effectively and stay informed by checking the detailed forecast at Port Moresby UV Index.
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September in Port Moresby, Papua New Guinea, shines brightly with 279 hours of sunshine, continuing the trend of abundant daylight that characterizes the region's dry season. As the year progresses, the city enjoys a steady increase in sunlit days, with August leading the year with 289 hours and October following closely with 288 hours. This gradual rise from the earlier months—where January begins with 212 hours—highlights a vibrant shift toward sunnier weather as the year marches on. With November and December promising even more sunshine, this period marks an ideal time to bask in the warmth and beauty of Port Moresby’s luminous skies.
In September, Port Moresby enjoys a 23% chance of sunny weather, marking a slight dip from the preceding months of July and August, which boast higher probabilities of sunshine at 35% and 27%, respectively. This trend reflects the shift from the drier winter months into the wetter season, as September approaches the rainy season in Papua New Guinea. While early spring brings a moderate likelihood of clear skies, it is essential to anticipate fluctuating conditions in the months that follow, particularly with October and November offering better chances of sun at 32% and 43%. As such, September serves as a transitional phase, navigating the balance between lingering winter sunshine and the impending rainy season.
As September unfolds in Port Moresby, Papua New Guinea, daylight begins to stretch its hours once more, returning to a generous 12-hour span after a few months of reduced light. This seasonal shift marks a transition from the more muted daylight hours of April through August, each basking in 11 hours of sunshine. With January through March consistently enjoying their full 12 hours, and the same pattern repeating in October through December, September acts as a bridge—offering a refreshing blend of abundant light after the winter months. This rhythm of daylight highlights the tropical climate’s unique ability to maintain a relatively stable day length throughout the year, making each September a vibrant encore of sunny days.
As September rolls in Port Moresby, Papua New Guinea, the winds begin to pick up, reaching an average speed of 5.0 m/s (11 mph)—the highest of the year. This increase signals a notable shift from the calmer months that precede it, where wind speeds hovered between 2.2 to 4.2 m/s. The distinct rise not only enhances the coastal breezes but also breathes life into the vibrant atmosphere, making it an ideal time for outdoor activities. Following September, the winds take a downward trend again, falling back to 2.5 m/s by October. Thus, this month stands out as a dynamic transition, inviting both locals and visitors to revel in the invigorating gusts while enjoying the captivating scenery.
Weather in Port Moresby varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Port Moresby, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather features milder temperatures with a minimum of 19°C (66°F) and an average of 25°C (78°F), while reaching a maximum of 30°C (87°F). It typically experiences around 81 mm (3.2 in) of precipitation over 11 days and maintains a humidity level of 80%. In contrast, January is warmer, with minimum temperatures around 23°C (74°F) and an average of 27°C (81°F), peaking at 33°C (91°F). The rainfall is significantly higher at 276 mm (10.9 in) spread across 22 days, accompanied by slightly increased humidity of 83%. For a more detailed understanding, check the Port Moresby weather in January.
When comparing the weather in September and February, notable differences emerge in temperature and precipitation. September experiences milder temperatures, with a minimum of 19°C (66°F) and an average of 25°C (78°F), while February boasts warmer conditions, marked by a minimum of 23°C (73°F) and an average of 27°C (81°F). Additionally, February is significantly wetter than September, as it receives about 200 mm (7.9 in) of precipitation over 21 days, compared to September's 81 mm (3.2 in) over just 11 days. Humidity levels are slightly higher in February at 84%, compared to 80% in September. For a detailed analysis of February's weather in Port Moresby, check out Port Moresby weather in February.
When comparing the weather in September and March, one can observe some notable differences. September generally has milder temperatures, with a minimum of 19°C (66°F) and an average of 25°C (78°F), whereas March features warmer conditions, with a minimum of 23°C (74°F) and an average of 27°C (80°F).
In terms of rainfall, March is significantly wetter, receiving 307 mm (12.1 in) of precipitation over 28 days, compared to September's 81 mm (3.2 in) over just 11 days. Additionally, humidity levels are slightly higher in March at 84%, compared to September's 80%. For more detailed insights into March weather, you can check Port Moresby weather in March.
In September, the weather tends to be warmer with average temperatures ranging from a minimum of 19°C (66°F) to a maximum of 30°C (87°F) and average humidity at 80%. In contrast, April experiences slightly higher temperatures, with minimums of 22°C (72°F) and maximums reaching 31°C (88°F), but it also sees significantly more rainfall, totaling 215 mm (8.5 in) over 24 days, compared to September's 81 mm (3.2 in) over just 11 days. This increase in precipitation makes April feel more humid, with an average humidity of 86%. For more details, you can check Port Moresby weather in April.
In September, the weather tends to be slightly milder compared to May, with average temperatures ranging from a minimum of 19°C (66°F) to a maximum of 30°C (87°F). The humidity is also lower at 80%, accompanied by 81 mm (3.2 in) of rainfall over approximately 11 days. In contrast, May features warmer temperatures, with a minimum of 22°C (72°F) and a maximum reaching 31°C (89°F). This month sees increased precipitation at 95 mm (3.8 in) over about 13 days, and humidity is higher at 88%. For a more detailed look at May weather, you can check this link: Port Moresby weather in May.
In comparing the weather of September and June, both months feature similar maximum temperatures, reaching up to 30°C (87°F), but September tends to have a slightly higher average temperature of 25°C (78°F) compared to June's 26°C (79°F). June experiences slightly warmer minimum temperatures, averaging 21°C (70°F), while September starts at a minimum of 19°C (66°F). Precipitation is also noteworthy; September sees higher rainfall with 81 mm (3.2 in) over 11 days, while June has less, with 63 mm (2.5 in) over 9 days. Additionally, humidity is higher in June at 88% compared to September's 80%. For a more detailed overview, check out Port Moresby weather in June.
September and July in Port Moresby exhibit similar average temperatures, with July recording a slight increase in minimum temperature at 20°C (69°F) compared to September's 19°C (66°F). Both months have the same average high of 30°C (86°F in July and 87°F in September), indicating a consistent warmth. However, September tends to be wetter, with 81 mm (3.2 in) of precipitation over 11 days, whereas July experiences only 45 mm (1.8 in) of rain across 8 days. Additionally, humidity levels are marginally higher in July at 87%, compared to 80% in September. For more details about July weather, you can check Port Moresby weather in July.
September shows slightly cooler temperatures compared to August, with a minimum of 19°C (66°F) down from August's 21°C (69°F), while the average remains the same at 25°C (78°F) and the maximum reaches a comfortable 30°C (87°F) compared to August's 30°C (86°F). Rainfall increases in September, totaling 81 mm (3.2 in) over 11 days, compared to August's 58 mm (2.3 in) over 10 days. Additionally, humidity is slightly lower in September at 80%, compared to 85% in August, making for a marginally less sticky atmosphere. For more details, view the Port Moresby weather in August.
In September, the weather features a minimum temperature of 19°C (66°F) and an average of 25°C (78°F), with a maximum reaching 30°C (87°F). During this month, there is 81 mm (3.2 in) of precipitation spread over 11 days, and humidity hovers around 80%. In contrast, October sees a slight increase in temperatures, with a minimum of 21°C (70°F), an average of 26°C (79°F), and a maximum of 31°C (88°F). However, it experiences more rain, totaling 119 mm (4.7 in) over 17 days, accompanied by a humidity level of 81%. For a detailed look at the weather patterns during this time, you can check Port Moresby weather in October.
September and November display distinct weather patterns. In September, temperatures range from a minimum of 19°C (66°F) to a maximum of 30°C (87°F), with an average of 25°C (78°F). The month experiences about 81 mm (3.2 in) of precipitation over 11 days, accompanied by a humidity level of 80%. In contrast, November brings slightly warmer conditions, with temperatures varying from a minimum of 21°C (69°F) to a maximum of 33°C (91°F), averaging 27°C (80°F). This month is also wetter, receiving 130 mm (5.1 in) of rain across 17 days, while humidity remains relatively high at 81%. For a more detailed look at November weather, you can visit Port Moresby weather in November.
In September, the weather typically features milder temperatures, with a minimum of 19°C (66°F) and an average high of 30°C (87°F), alongside substantial humidity averaging around 80%. Rainfall during this month totals approximately 81 mm (3.2 in) over about 11 days. In contrast, December sees warmer temperatures, with a minimum of 23°C (73°F) and an average maximum of 33°C (93°F), while also experiencing increased precipitation of 169 mm (6.7 in) spread out over 22 days. The humidity rises slightly to 83%. For more detailed information, you can check Port Moresby weather in December.
As September unfolds in Port Moresby, the climate offers a delightful blend of warmth and humidity. With maximum temperatures reaching a comfortable 30°C and an average of 25°C, the month experiences mild days compared to the hotter peaks of the dry season. While rain becomes more frequent with about 11 days of precipitation, the overall total remains moderate. This increase in rainfall contributes to a lush atmosphere, contrasting the dryness of the preceding months. For those seeking to plan their visit or simply learn more about what to expect, more insights can be found at Port Moresby Climate.