Tonga Meteorological Services have issued a storm warning for Ha'apai, and storm-force winds, heavy rain and possible flooding are expected to batter much of Tonga, in the nex 48 hours, 16-17 June 2026.
Meteorologists upgraded weather alerts placing Ha'apai under a storm warning. While storm-force winds warnings remain for Tongatapu and 'Eua.
Forecasters say a low-pressure system located west of Fiji is moving slowly southeast and is expected to intensify weather conditions across Tonga through Wednesday.
Ha'apai, Tongatapu and 'Eua
Residents in Ha'apai, Tongatapu and 'Eua may expect fresh to strong easterly and northeasterly winds strengthening to destructive storm-force gusts at times. The weather system is expected to bring widespread cloud, heavy rain and thunderstorms, increasing the risk of flooding in low-lying areas.
Marine conditions are also forecast to deteriorate significantly, prompting authorities to maintain storm warnings for coastal waters around Tongatapu, 'Eua, Ha'apai and offshore areas including Tele-ki-Tonga and Tele-ki-Tokelau.
Vava'u and Niuas
Heavy rain warnings and flash flood advisories have been extended to the Niuas and Vava'u, and gale warnings remain in place for these islands. Where damaging gale-force winds, heavy rain and thunderstorms are expected. A high surf warning and extreme high tide alert remain in force across all Tongan coastal waters, with officials warning of possible seawater flooding in vulnerable coastal communities.
Meteorologists forecast winds of 20 to 30 knots across much of the kingdom's waters, with gusts reaching between 45 and 55 knots in storm-affected areas. Seas are expected to become very rough to high, reaching up to five metres, accompanied by large easterly swells of up to four metres.
A small craft advisory remains in effect nationwide, with mariners urged to remain in port and avoid unnecessary travel at sea.
Conditions are expected to gradually improve from Thursday, particularly across Tongatapu and 'Eua, where winds are forecast to ease and showers become more isolated. However, unsettled weather is expected to persist over Vava'u, Ha'apai and the Niuas, with periods of heavy rain and isolated thunderstorms continuing.
The weather office said the situation remains under close monitoring and advised the public to stay updated with the latest forecasts and warnings.
