A tropical cyclone formed near Fiji has strengthened overnight, with forecasters predicting it will intensify further as it moves toward New Zealand.

Tropical Cyclone is now category 2 strength, with sustained winds at 93km/h rising to more than 100km/h later today, the Fiji Meteorological Service reports.

Its is tracking toward New Zealand, with the Joint Typhoon Warning Center forecasting its centre to be 400 to 600kms off the East Cape by the middle of next week.

WeatherWatch.co.nz has warned of dangerous surf rips and heavy surf in the East Cape, Gisborne and Hawkes Bay beaches next week.

The storm system could also bring severe gales or heavy rain, the forecaster predicted.

Its head analyst Philip Duncan said the path of the newly formed cyclone would likely be similar to that of ex-tropical cyclone Atu, which passed east of New Zealand in late February.

That week, 11 students were rescued from a rip south of Napier.

"Traditionally in New Zealand the news headlines tend to be around cyclones hitting us - but in reality the offshore ones can pose the same risk to life due to dangerous rips and waves.

"These storms don't need to affect our weather to make our beaches deadly."

Metservice weather ambassador Bob McDavitt said the cyclone could bring big surf to the last stages of the Cold Water Classic surfing competition in Gisborne.

Meanwhile, a front moving over the Tasman Sea is expected to bring heavy rain to the central North Island and lower South Island over the weekend.

The rain is expected to hit hills near Nelson on Saturday before spreading to the Tararua Range, eastern Taranaki, Raglan and Tongariro National Park.

A severe weather warning has been issued for Mt Taranaki.