September can still be quite wet, but toward the end of the month rainfall may begin to lessen in places. Sea conditions improve only gradually as the dry season approaches.
Matt Kieffer CC BY-SA 4.0 Wikimedia Commons
Average daily low and high (°C) and monthly rainfall. The badge shows how it feels, allowing for humidity.
Average temperature across Marshall Islands in September.
capital and nearby lagoons
September begins a gradual easing: rainfall may still be common but long sunny stretches reappear more often, and the ocean has begun to calm compared with midsummer. This is a good time for cultural visits and lagoon fishing charters when operators resume more reliable schedules. Crowds are low; accommodation prices are modest and you can often negotiate for last-minute boat seats if you stay flexible.
Ebeye, Kwajalein Atoll, nearby dive sites
September shows the first hints of improving conditions; rainfall frequency may dip and long sunny runs return more often, making dives and lagoon trips more appealing. Marshaling longer excursions becomes easier as captains find more dry days, but still expect portable, rapid rain in the afternoons. Keep anti-corrosion care for cameras in mind - salt spray mixed with frequent showers can be hard on gear.
atomic-test sites and expedition diving
September slowly brings more reliable windows again as rainfall frequency can taper and trade winds begin to re-establish. Expedition operators start planning longer routes; if you time a trip on a run of dry days you can take advantage of clearer seas and superb underwater light. Remember that even in improving conditions, remote atolls have minimal services - bring spare supplies and expect no conveniences.
Jaluit, Mili, Ailinglaplap and quieter outer islands
September hints at improvement as dry periods lengthen and the sea calms, making inter-atoll travel simpler and diving visibility more reasonable. The quieter islands begin to feel more accessible, and local homestays re-open more services. If you want solitude with improving weather, this month can be rewarding - still bring waterproof gear for occasional showers.
There are no major festivals or events in Marshall Islands during September to be aware of.
See how September compares with the rest of the year, then read the full guide.