If May was defined by mountainous high pressure, June is defined by much more variety. If you need rain, this is better news. We’re seeing more chances for rain this week as high pressure is replaced by low pressure.
Across 2024 we’ve seen a lot of high pressure and much of this has been connected like a chain-link fence. From the Indian Ocean to Australia/New Zealand to South America these powerful highs, connected to El Niño, stopped rainmakers from properly entering NZ.
El Niño has gone but the hangover remains. By that I mean just because the El Niño party has come to an end it doesn’t mean the house is clean from the party … so it takes time to see those powerful highs break apart.
That’s why the rainmakers now developing are a sign of more than just winter arriving. They are also a sign of the heavy high pressure zones of El Niño finally breaking apart too.
In fact, this is the main reason WeatherWatch pushed back so hard two months ago against mainstream news outlets who immediately switched from squawking breathlessly about El Niño to flapping incessantly about the incoming La Niña.
Like turning a giant cargo ship around, this isn’t a quick and instant procedure. In fact, there’s a real possibility it could take the rest of this year. In our recent June ClimateWatch update (where we look at monthly and seasonal weather trends) the Bureau of Meteorology (BoM) out of Australia isn’t even expecting La Niña by as late as October.
However, NOAA in the United States is, along with the United Kingdom Met Office. But Europe, Japan, France, and Aussie aren’t in agreement. The mean result? By the middle of spring we’re leaning towards La Niña but still not officially there. In fact, long-range computer models flatline in the “neutral” zone for months ahead.
What does this all mean for NZ? It means we can forget about El Niño and La Niña for now! It means we’re in a neutral period of weather creating chaos and variety. It means rather than a “normal winter” we probably have a slightly drier and milder one – but the chaos factor is the biggest change we’ve seen this year to our weather patterns and means that regions that are dry do have some better chances of wet weather.
Over the next 15 days we see rain coming back. It’s messy but between our mountains and ranges and the broken rain bands we expect between 30 and 150mm across the nation.
The lowest totals look to be in Bay of Islands, Hawke’s Bay, Wairarapa and North Canterbury.
Rainwise, think of NZ as a white canvas and someone is flicking dripping paint brushes repeatedly at it. At first it doesn’t colour it in – but over time it starts to change.
Upcoming Highlights
• Monday, a cold front/rain band clears NZ
• Colder air moves up NZ in Tuesday
• On Thursday, northwesterly winds for many ahead of low
• Friday to Sunday, low pressure dominates
