The 2025–26 South Pacific cyclone season is an active tropical weather period occurring in the southern hemisphere over the South Pacific Ocean, east of longitude 160°E. Officially, the season began on 1 November 2025 and will run through 30 April 2026, although tropical cyclones can form at any time between 1 July 2025 and 30 June 2026 and still count toward the season’s totals. The season was seen to be ongoing, even through late December 2025, with multiple early systems recorded, but no fully developed tropical cyclone had entered yet.
While most tropical cyclones in this part of the Pacific are monitored by a network of meteorological agencies, the Fiji Meteorological Service (FMS) serves mainly as the Regional Specialised Meteorological Centre (RSMC) for the central as well as eastern South Pacific, issuing official warnings and assigning systems with an “F” suffix. The Australian Bureau of Meteorology (BoM) and New Zealand’s MetService also contribute to forecasts and warnings, especially when systems move west or south into their areas of responsibility. Additionally, the United States Joint Typhoon Warning Center (JTWC) tracks the basin for American interests, though its advisories are considered unofficial for the South Pacific basin.
Before the season began, regional forecasts issued by agencies including the FMS and New Zealand’s Earth Sciences New Zealand (ESNZ) projected a moderate level of cyclone activity.
Taking into account these reports, at least four to five tropical cyclones were expected to arrive in these areas, with one to three potentially intensifying into even more severe tropical cyclones on the Australian tropical cyclone intensity scale. Longer‑range forecasts from ESNZ suggested slightly higher activity in terms of overall storm counts, predicting that there would be about five to nine cyclones within the broader southwest Pacific portion of the area. These forecasts considered waning oceanic and atmospheric patterns, including a potential neutral to weak La Niña influence that can enhance cyclogenesis in certain parts of the South Pacific.
Climatologically, the South Pacific cyclone season experiences peak activity from January through March, when ocean waters are warm and atmospheric conditions are most favourable for tropical development. Sea surface temperature anomalies, low vertical wind shear, and the location of the South Pacific Convergence Zone (SPCZ) all play important roles in where and how storms develop. Warm waters provide the energy needed for cyclones to intensify, while the SPCZ can act as a breeding ground for disturbance formation.
As of the end of December 2025, the basin had already seen several tropical systems form. RSMC Nadi and JTWC have been monitoring numerous tropical disturbances and depressions, which are precursors to full cyclones. The first recorded system formed on December 3, 2025, and was designated Tropical Disturbance 01F. It did not intensify into a named storm. Other early systems, such as 02F and 03F, developed as tropical depressions, bringing varying degrees of unsettled weather to parts of the region, including French Polynesia, the Solomon Islands, Vanuatu, and Fiji. Another disturbance, 04F, was active as of late December 2025, located near Samoa and American Samoa.
None of the early disturbances had reached tropical cyclone intensity, defined by sustained winds above 35 knots, and none received official names. The season’s strongest system to date had modest central pressure and remained below cyclone strength. No fatalities or economic damage have been reported, though monitoring continues. When a tropical depression reaches the required intensity, it is named from the South Pacific list, including Urmil, Vaianu, Wati, Xavier, Yani, and Zita. Communities remain observant, with meteorological services providing forecasts and warnings for rainfall, strong winds, high seas, and even storm surge.
Preparedness and early warnings remain crucial as the South Pacific braces for potential cyclones, protecting lives, property, and communities.
