Papua New Guinea in May: Weather, Crowds & What to Expect

The Highlands (Mount Hagen, Goroka, Mt. Wilhelm)

Dry-season conditions start to assert themselves from May-mornings in Mount Hagen and Goroka are cool and increasingly crisp while daytime temperatures become comfortable for long treks. The trails firm up and visibility improves on high ridges, which is why trekking and the coffee-plantation visits pick up from May through September. Pack warm layers for cold nights (fleece and hat), and note that higher passes can have frosty mornings in June and July.

Southern Coast & Port Moresby (Papuan Gulf, Gulf Province)

With May the southern lowlands settle into their calmer, drier months; Port Moresby becomes noticeably less humid and sea conditions improve for snorkeling and short cruises to Motupore Island. Daytime temperatures are warm but tolerable; mornings and evenings are pleasant for walking the harbor. This is a good window for overland trips toward Gulf Province before the rains return-pack light layers and reef shoes for improved water clarity.

Trans‑Fly & Western Lowlands (Fly River, Western Province, Trans‑Fly)

May marks a significant change as the Trans‑Fly enters the dry season: floodplains begin to reveal sandbars and grasslands dry out, making remote plains and wildlife salt pans accessible by road and four‑wheel drive. This is one of the best times to see waterbirds congregating and for terrestrial wildlife to use remaining waterholes. Travel is easier but bring dust protection and be ready for long drives on corrugated tracks.

Northern Coast & Sepik (Madang, Wewak, Sepik River)

By May the northern coast often slips into a relatively drier window: Madang and coastal sites see fewer prolonged storms and river levels start to recede in the Sepik mainstream. Beaches and coastal reefs regain some clarity making reef trips from Madang more pleasant; overland bush tracks gain reliability. Still pack insect protection and plan river visits around water receding to avoid logistical surprises.

Bismarck & Solomon Islands Region (New Britain, New Ireland, Manus, Bougainville)

May begins the drier and more settled months for much of the Bismarck archipelago; Kimbe and Rabaul see fewer afternoon storms and diving visibility improves, especially for trips to volcanic reefs. Warmer days and calmer seas make shoreline exploration and trekking to inland crater lakes more practical. Bookings pick up for sportfishing and whale-watching excursions-bring sun protection and reef footwear.