TROPICAL Cyclone Oma formed near Vanuatu on Tuesday and will bring days of torrential rain and strong winds to the islands this week.
The slow movement of this storm will bring dangerous weather to the country into this weekend, heightening the risk for flooding, damaging winds and power outages.
The heaviest rain is currently expected to remain north of Erromango into Friday, affecting the islands of Efate, Epi, Ambrym, Malekula, Pentecost, Ambae, Maewo and Espiritu Santo.
These areas can expect widespread rainfall of 100-200 mm through Friday, with local amounts over 300 mm.
Mudslides will also be a concern across the rugged terrain of the islands. Some roadways could be blocked for days following the storm.
As Oma slowly tracks eastward, a landfall is not out of the question on Espiritu Santo by Thursday before Oma begins to turn more southward.
Regardless of if landfall occurs, Oma is expected to track close enough to several of the islands to produce damaging winds.
Malekula and Espiritu Santo are currently at greatest risk for damaging winds; however, any shift in Oma’s track can have a dramatic effect on where damaging winds occur.
Rough seas and dangerous rip currents will also be a concern for Vanuatu and New Caledonia, with seas over 6 metres possible in northern Vanuatu.
In the longer range, Oma is forecast to track southward toward New Caledonia with the potential for a direct strike on Grand Terre during the weekend.
Impacts ranging from damaging winds and power outages to flooding and mudslides will be possible across the country.
Oma may end up stalling over the region into next weekend furthering the risk for dangerous weather.
Elsewhere, a tropical low pressure, located near Fiji, will track southwestward in the coming days, bringing a prolonged period of unsettled weather from Fiji and Tonga to American Samoa.
Development into a tropical cyclone is not expected during this time; however, gusty winds will be possible in any showers and thunderstorms as the storm impacts the region.
The greatest concern will be for flash flooding, as most locations can expect 50-100 mm (2-4 inches) of rain through Friday. However, hardest-hit areas can receive up to 300 mm (12 inches) of rainfall, with 50-75 mm (2-3 inches) falling within a 12-hour period.
Areas most at risk for this torrential rainfall include Wallis and Futuna, Tonga and northeast parts of Vanua Levu.
Unsettled weather is forecast to continue from Fiji to American Samoa and Tonga into next week along with the risk for another named tropical cyclone to develop in the region.