The large high that brought us not only our big snow storm last week but temperatures over 20 degrees this week, is finally starting to move out into the Pacific Ocean.

The centre of the high – which yesterday crossed Auckland and Northland bringing plenty of anti-cyclonic gloom, is today mostly to the east of Northland – although a smaller, secondary bubble of high air pressure exists just to the west of Auckland.

By tomorrow the high will continue to slowly trek eastwards slowly lowering the air pressure over the country.  So what does that mean?  Well the lower the air pressure the more unstable the weather can be – ie, lows can move in, strong winds and heavier rain are more likely.

But nothing stormy is in the forecast for the next few days – apart from the possibility of some heavy rain in northern New Zealand.  This is due to a small area of low pressure that has hounded Queensland all week with heavy bands of rain and showers.  It isn’t a large low but the rain within it is sub-tropical, slow moving and heavy.  There may be pockets of heavy rain later this weekend in the Far North – and we’ll keep you posted.

Meanwhile in the South Island the early spring westerlies continue with another surge of wind pushing back in again later today and during Friday.  While it’s unexpected to be too blustery in most main centres the wind flow could again see some localised areas hitting the 20 degree mark (or higher) in eastern areas – but it all depends on the exact wind direction, speed and timing.  It’s these three factors which can often make calling Christchurch’s high so tricky.  In some cases places like Darfield can be 22 degrees while Christchurch is on 14… due to the warm winds not hitting the city, either due to lack of strength or just slightly the wrong wind direction.  The nor’west arch – a band of cloud that appears during a nor’wester – can also block the sun and hold back the temperatures until it passes.

The warm South Island winds will come and go over the next few days at least.

Who has what today?

• Sunniest – Eastern New Zealand from Southland to East Cape
• Windiest – Southern tip of both islands, also around the Southern Alps.
• Cloudiest – Northern NZ and West Coast
• Wettest – West Coast
• Warmest – Canterbury
• Coldest – West Coast

– WeatherWatch.co.nz