Sub-tropical air is today spilling down over the country – and will increase further over the next 24 hours predicts WeatherWatch.co.nz.

For those in the upper North Island it means the rain clouds are building – with heavy falls expected later today, overnight and tomorrow. 

In the South Island it may not be quite as hot, with winds drifting in from the north east for many.  Conditions will remain humid and cloudy for many eastern areas.

The sub-tropical air will peak over the country on Thursday – with WeatherWatch.co.nz saying afternoon heating could again create thunderstorms over the North Island.

But the humid air won’t linger – thanks to a new high and deepening low.

The new high will be pushing in from the south west – bulldozing the wet, humid, weather east of the country on Friday – and replacing it with a fresher south wester.

However an aggressive low pressure system to the east of the South Island will help strengthen those winds further. 

Latest modelling suggests the low won’t linger and will quickly deepen then drop over the Southern Ocean – but for Saturday it will create strong winds around the eastern South Island and lower North Island.

– Homepage image / File, David Hawke

– WeatherWatch.co.nz