A battle of weather systems this Easter Weekend
The Southern Ocean will be stormy this weekend but latest modelling shows high pressure will not give up easily, pushing back in a battle between weather systems.
As WeatherWatch.co.nz said last week Easter Weekend could be stormy with very low pressure expected in the Southern Ocean.
"We’re now getting closer to be able to lock in severe weather risks and increasingly high pressure is trying to ‘knock’ stormy weather further south.
"Computer modelling has been messy as it tries to work out the complicated set up. This “battle” helps create a ‘squash zone’ of air pressure – making for windier weather."
But high pressure – which has dominated northern NZ for so many months a drought has formed and remains in place – is not wanting to let this stormy weather set in, says WeatherWatch.co.nz
High pressure remains to the north of NZ keeping a ‘lid’ on how far Southern Ocean weather will spread up the country.
“We’re seeing some sunny, calm, weather this long weekend and we’re seeing some severe weather risks too – in both islands. It’s not a whole weekend of stormy weather, it’s unsettled with a burst of severe weather in some regions on Sunday and Monday,” says head forecaster Philip Duncan.
The main surge of weather will be on Easter Sunday and Monday – with the coolest change arriving on Monday.
Thursday and Good Friday look windy, mainly in coastal NZ with sou’westers blowing up to gale force.
Saturday looks a little windy, but gales are less likely.
Gusts on Sunday PM may reach over 120km/h in some exposed places, possibly even over 150km/h in some very extreme exposed areas in the south, especially if an area of deep low pressure ends up hugging the Southland coastline on Sunday.
Easter Sunday looks calmer in the North Island at first but gales, gusting severe, may push into the lower South Island, surging over the North Island later.
Easter Monday looks colder and windy nationwide, but winds do ease back a little later in the day – especially in the upper North Island. Gales are likely in many coastal, hilly and exposed areas.
This weather may be quite gusty with some calm times too.
The main surge of cold weather will be on Easter Sunday and Monday. It’s likely to be mild.
It’s possible winds on Sunday or Monday may be strong enough in some places to knock out power.
"With COVID-19 meaning most of us are in lockdown at home, it’s worth thinking about what supplies you may need should the weather become more severe than forecast this Sunday and Monday.
"For the most part winds will be below damaging but this system is very large with many moving parts.
"Being prepared helps lower anxiety."