Papua New Guinea in September: Weather, Crowds & What to Expect
Climate Map for September
Average temperature across Papua New Guinea in September.
City Weather in September
| City | High | Low | Rain | UV | Feels |
|---|---|---|---|---|---|
| Port Moresby | 30° | 23° | 47 mm | extreme | Warm |
| Lae | 29° | 22° | 344 mm | extreme | Warm |
| Arawa, Bougainville | 30° | 23° | 273 mm | extreme | Warm |
| Mount Hagen | 24° | 12° | 190 mm | extreme | Mild |
| Popondetta | 31° | 21° | 172 mm | extreme | Warm |
| Madang | 30° | 22° | 159 mm | extreme | Warm |
| Mendi | 23° | 12° | 249 mm | extreme | Cool |
High / low are average daily temperatures (°C). “Feels” reflects how hot or cold it feels, allowing for humidity.
The Highlands (Mount Hagen, Goroka, Mt. Wilhelm)
September keeps the clear, dry pattern and is one of the busiest months - Goroka Show and other cultural events bring visitors from across PNG, filling guesthouses and charter flights. Trails onto higher ridgelines are stable and visibility for birdwatching is excellent; streams are lower but still flowing. Travel costs and competition for guides rise, so reserve festivals and flights months ahead.
Southern Coast & Port Moresby (Papuan Gulf, Gulf Province)
September’s late dry-season warmth brings clearer seas and less humidity, and it’s a practical time to reach remote coastal PNG communities by boat or plane. Reef snorkelling around the Gulf often gives good visibility; mainland tracks remain firm. Be aware that some local festivals are scheduled now, meaning more domestic flights and accommodation pressure in the capital.
Trans‑Fly & Western Lowlands (Fly River, Western Province, Trans‑Fly)
September’s late dry conditions mean the landscape is at its most exposed: salt pans and grasslands are dry, and the chance to see ground birds and mammals increases as water concentrates in fewer pools. Local festivals sometimes coincide with better access, drawing domestic visitors; accommodation remains basic and often booked. Watch for controlled burns and haze on prolonged dry spells.
Northern Coast & Sepik (Madang, Wewak, Sepik River)
September remains mostly dry and warm; travel is straightforward and river levels are lower, revealing sandbars and riverbank villages clearly. The accessibility makes it a popular time for organized cultural tours and amateur ethnographers; lodging fills in Wewak and Madang for major events. Keep insect repellent handy when on dusk riverbank walks as mosquitoes return as water pools linger.
Bismarck & Solomon Islands Region (New Britain, New Ireland, Manus, Bougainville)
September’s late dry-season warmth continues, with generally calm seas and reliable small-plane services between Kavieng, Kimbe and Rabaul-ideal for island-hopping. Southern Bougainville and Manus remain accessible, and ceremonies or market events can draw visitors. Remember that the sun is intense; coral-safe sunscreen and good reef footwear remain essential for beach and snorkel days.