Ten years ago, DOC worker Bruce Knight used to do his bit for the MetService marine forecast by leafing through a book of cloud photos until he found an image that matched what he could see in the skies above Stephens Island in the Marlborough Sounds.
At times, said Knight, who was posted on the tiny tuatara sanctuary from 2000 to 2003, it was guesswork, a case of "holding the book up towards the sky and saying 'that looks like the one – round and fluffy'."
Four times a day he'd cloud-spot, read some wind and rain instruments, then phone it through to the MetService, who'd fold it into their forecasts.
Times have changed. Now, most Stephens Island data comes continuously from an unmanned weather station. And you can get a forecast whenever you want.
On Thursday, I pressed a button on my smartphone and asked: “What will the weather be like tomorrow?”.
The phone beeped and whirred then replied in its strangely constipated male English voice: “The weather's looking good tomorrow. Up to 18 degrees and sunny”, and the screen flashed up a five-day forecast.
Weather forecasting has, in other words, got pretty fancy. In fact, says Wellington meteorologist Ramon Oosterkaamp, that iPhone forecast isn't great.
The data is free from the United States government's supercomputer-driven Global Forecast System (GFS), and is nowhere near as accurate as data from our own MetService, which has more local data, and refines the coarse planetary models with high-res local models. He would say that though – he's MetService's manager of Public Weather Services.
The point, though, is that you can pick and choose. Weather's online, in print, on radio, on TV. Forecasts come from the MetService or from the US or from private firms like Auckland's WeatherWatch. If you're a horticulturist you can hire a niche frost forecaster like Hawke's Bay's Metris. You can DIY: join the weather-watchers who invest a few grand in a weather observation station in their own back garden. Or you could just squint at the clouds and take a guess. The only thing you can't do is expect anyone to give you a 10-day forecast that's actually reliable.
On a changeable Wellington morning last month, Oosterkaamp showed the Sunday Star-Times around MetService's head office in Kelburn, an ugly building with beautiful views across the city and harbour.
Worldwide, the accuracy of weather forecasts is improving says Oosterkaamp, but slowly.
Looking 10 days into the future "is still pretty much our limit".
Meteorology leapt forward mid-century with the advent of radar and weather satellites, but for the past 30 or 40 years, accuracy has improved at "about a day every 10 years," says Oosterkaamp.
"So the accuracy of day four – that was the accuracy of day three 10 years ago."
Supercomputers predict weather by churning out numerical solutions to physics equations governing movement of air and moisture on a warm, spinning planet.
Improvements are still coming from placing weather stations closer together and running models on tighter grids, but the atmosphere is still a chaotic system, which means tiny differences in starting conditions lead to radically varying predictions.
You still need trained forecasters with experience and intuition to second-guess the supercomputers. The MetService is the 800lb gorilla of New Zealand's forecasting ecosystem.
Forecasting was a division of the Transport Ministry until 1992, when MetService was founded as a SOE and told to make a profit (a demand that still rankles with some weather enthusiasts).
Now it employs 200 people worldwide and had revenues of $38 million in 2010. MetService feeds government and industry the information needed to run our roads, airways and sea lanes safely, to plan hydroelectric generation, to run our farms and so on. But it also makes a buck selling forecasts to media and has developed a whizzy weather graphics package used by broadcasters here and abroad, including the BBC. There's more.
"We're the only entity," says Oosterkaamp proudly, "that can broadcast weather warnings for the New Zealand landmass. It requires a substantial amount of knowledge and skill to do that; you can't just have general people doing that."
If your picnic gets washed out because of a dud forecast, "it's disappointing", says Oosterkaamp. But if there's heavy rain or snow on the way, or gales in the Foveaux Strait, that's a matter of public safety, and they have to get it right.
In March, when there was a deep, nasty low heading in, MetService called Taupo's Ironman organisers and persuaded them to reschedule to avoid severe gales.
Dan Corbett, MetService's media “ambassador” chips in: “We're far more engaged and proactive [than other state broadcasters]. You'd never see the UK Met Office or the US National Weather Service call up a sporting event, to say 'this will be a dangerous situation'.”
Corbett is MetService's new star signing. A trained meteorologist, he was one of the BBC's top television weatherman until he moved to New Zealand early last year.
Like his big-bearded predecessor, Bob McDavitt, Corbett is always available for media comment on the latest weather bomb.
But unlike McDavitt, the 45-year-old is a broadcaster in his own right. So each day he nips down to MetService's tiny television studio and knocks out a range of short forecast videos which are posted online and pushed to a smartphone app.
He doesn't use a script, seldom needs a second take, and uses some of the weirdest descriptions of weather you've ever heard. The Radio Times called Corbett “Britain's best weatherman”.
One English fan, who is presumably bonkers, is still running the fan blog she launched in 2006, which includes daily summaries of his forecasts and transcripts of what she calls “Dan-isms”.
These include recurring use of weather metaphors including a two-legged octopus, a washing machine, treacle on a pudding plate and a broken neon sign.
Corbett said when a forecast was dull, viewers tune out halfway. His mad banter is the antidote.
It's “theatre of the mind”, said Corbett.
“So I'll say: ‘The weather system is stuck. You drive a car on the beach and it just sits there and spins its wheels in the mud. It's not going to move.'
“People see the car, vrrrroooom. And they think of the weather system. They may not understand the science but now they can see it"
Corbett says the MetService is colonising the new territories of smartphone apps and social media, and offering more and more information on its website, because “all the different platforms are ways to get important information out”.
Aucklander Phil Duncan would also like to take a little credit for MetService's increasing sexiness.
He's the founder of weather watch.co.nz. He said since he came on the scene seven years ago, offering rival forecasts and giving the online audience what it wanted, MetService has lifted its game to match.
Duncan launched the bright and breezy site - which has forecasts and maps and encourages readers to chat about weather and post pictures - after seeing how fascinated Kiwis were by the catastrophe of Hurricane Katrina in 2005.
Now he gets 50,000 to 100,000 unique visitors a month, has a handful of staff around the country, and a few private forecasting clients.
He writes a weather column for the New Zealand Herald and, like Corbett, is always available for media soundbites on weather.
Duncan holds the MetService in high esteem, but is dark on a state-funded forecaster charging for data. In Australia and the US, said Duncan, they give it away, allowing proper competition with private forecasters.
In April, he lodged a Commerce Commission complaint over MetService's demand for $30,000 a year for its national temperature readings. He has also lobbied MetService to supply raw data from its rain radars, with only partial success.
Corbett agreed that in an ideal world, MetService would give away more data, but he said budgets here are tighter than abroad and, as an SOE, MetService had to make money.
Despite his smaller information base and lack of formal training, Duncan said his forecasts are pretty good, especially for Auckland weather. Small operators like him have the benefit of “super-local knowledge”.
Zoom in even closer - let's call it hyper-local - and you'll find the true weather nuts: the people so fond of rainfall and lightning-strike data that they collect their own.
Take Willoughby Owen. He's 24, and seven years ago set up his own weather station in Hamilton - solar sensor, thermometer, anemometer, lightning detector, rain gauge and humidity meter - and put the data online at hamilton weather.co.nz.
It's not really about forecasting, more about collecting the data (and filling the gaps left by MetService, who didn't used to share their airport wind information).
Willoughby loves his weather so much that in 2008 he moved to Darwin for the thunderstorms, leaving a friend to mind the weather station.
He gets by with a hotel reception job, but lives for the storms. His favourite? “December 10, 2009. It was like bombs going off everywhere, and lightning smashing into our apartment complex. It was very awesome.”
He has also made four storm-chasing pilgrimages to the US with weather-watching mates. One year they drove 26,000km in six weeks chasing tornadoes.
Ricky Huntington took his weather obsession one step further. An electronics whiz and audio engineer (he recorded OMC's hit single How Bizarre), Huntington lives in Auckland's Grey Lynn, where just like Owen he collects data from a personal weather station and puts it on his website (greylynnweather.net). But Huntington also dabbles in forecasting, and is weatherman for student radio station bFM.
There's no money in it, but it gives him a kick when, after a particularly vicious storm or freak event, traffic to his pretty basic site leaps from a couple of hundred to several thousand visits a day.
He also gets a surprisingly large number of requests from insurance investigators seeking confirmation that there was indeed a big wind gust in Grey Lynn on so-and-so day at such-and-such time, as they check a policyholder's claim about a blown-off roof.
It's only a hobby, but Huntington says he spends a couple of hours a day on his forecasts, and many more just thinking about the weather.
“Every time I go outside I'm thinking about every cloud I look at - do I know what's going on there?”
All these weather-watchers love their data and their equipment, but like Bruce Knight holding his book of photos to the sky, they know that one of the oldest ways to read the weather is still the best: Look at the clouds.
Look, says Corbett, as he stands and points from the roof of the MetService office.
“That cloud is flat, almost like a pancake, so the air above it is probably warmer, so it's stable. But if those bottom clouds were like massive cauliflowers already, the forecaster would look and say we've got a very unstable regime, something's going to change.”
Corbett's favourite cloud?
“Big cu-nims” (that's meteorologist-speak for cumulo-nimbus, the unstable mushroom-shaped ones that can portend dramatic wind, rain and thunder).
“Naturally the cumulo-nimbus, which are responsible for thunderstorms.”
“Cumulo-nimbus. Nice anvil on the top. Real good thunderclouds.”
- © Fairfax NZ News
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