Severe Tropical Cyclone Zelia has today begun it’s weakening process as it races towards New Zealand but the latest prediction from the Fiji Meteorological Service is that it will retain a category 1 status as it approaches the upper North Island later tomorrow.

The tropical storm remains a “severe” Category 3 cyclone as it heads into Monday afternoon with winds averaging 148km/h and gusting well over 200km/h, according to various forecasting agencies.

Zelia’s central air pressure has also begun “filling in”. The latest reading by the Fiji Meteorological Service has it at 970hPa up from 957hPa earlier today.

WeatherWatch.co.nz says the cyclone is travelling incredibly fast towards New Zealand at a speed of 46km/h.

MetService weather ambassador Bob McDavitt told WeatherWatch.co.nz that Zelia is a “fast-mover” due to strong winds above the storm.

“It is embedded in a strong 30-40 knot (70km/h) flow aloft”.

“Zelia will not simply track downwind in this upper flow… The system is three-dimensional, and its track responds to lower level flows and surrounding systems as well” says Mr McDavitt.

Most international models show the storm retaining cyclone strength winds until it reachesnorthern New Zealand but due to the nature of tropical storms those strong winds lie right near the centre, away from land.

“Cyclones have the winds tightly wrapped right around the centre, unlike other lows that normally form around us, which don’t always have their strongest winds near the centre” says WeatherWatch.co.nz head weather analyst Philip Duncan.  “The severe gales might only extend one or two hundred kilometres from the centre, so if the storm remains more than that distance from land before being downgraded you can see how many regions will miss the damaging winds altogether”.

However latest data from the Fiji Meteorological Service shows the tropical storm will retain cyclone strength winds right up until tomorrow night as it nears the Far North.  The service predicts Zelia will be a category 1 cyclone with sustained winds of 65km/h and gusts to 120km/h as it nears the upper North Island later on Tuesday.

Map showing the predicted path of Zelia.  Times are UTC (add 13 hours for NZ) / Fiji Meteorological Service

The storm will continue to weaken rapidly as it crosses New Zealand on Wednesday morning says WeatherWatch.co.nz.

The combined lows are set to bring a period of heavy rain and increased humidity but WeatherWatch.co.nz says the system isn’t what they would describe as significant national event.  “It’s certainly one to watch and plan accordingly but most New Zealanders will experience just a fairly short lived spell of windy, wet, weather and by Wednesday the sun starts to come back out” says Mr Duncan.

MetService are likely to issue rain warnings today as the system approaches from the north.

– WeatherWatch.co.nz will continue extended coverage of the approaching lows over the next two days.