Impact of ex-Tropical Cyclone Evan

A deep low, formerly Tropical Cyclone Evan, lies about 1000 km northeast of North Cape and is moving slowly south. Over the weekend it is expected to swing southwest towards the North Island, passing not too far away from North Cape on Christmas Eve.

"Evan will bring a large amount of tropical air over New Zealand, which means the potential for heavy rainfall in places with strong onshore winds, " commented MetService Chief Forecaster Peter Kreft.

Over the northern half of the North Island, rain is expected to develop on Sunday. Heavy falls are likely in Northland on Sunday and Monday, and on Monday in the northern part of Auckland, Coromandel and western Bay of Plenty, and in the Gisborne district north of about Ruatoria.

In addition, winds over Northland and possibly Auckland are expected to be strong or gale northeasterlies. MetService has issued a Severe Weather Watch for the rain and wind, and it is very likely to be followed up by a Severe Weather Warning on Saturday.

"Christmas Day looks unsettled for many places," Kreft went on to say. "By this time Evan will be over the Tasman Sea, maintaining the warm, humid northerly flow over much of the country. Many New Zealanders will find the air very muggy. Rain over northern New Zealand will should have eased but not be completely cleared. However, rain is likely to spread into Nelson and the West Coast of the South Island. The driest places are likely to be in the east from Wairarapa to Canterbury."

Despite the likely unsettled nature of the weather on Christmas Day, it should be warm and not particularly windy in most places. "So, Christmas dinner outside isn't completely off the table for everyone," said Kreft.

Keep up to date with the latest forecasts and any watches/warnings at metservice.com or on mobile devices at m.metservice.com. You can also follow our updates @metservice on Twitter and MetService TV.

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