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Weather forecasts are horribly inaccurate.

WEATHER FORECASTS were always things for older people, like manners and leaf tea. And indeed for olden days: D-Day was only possible because of some superhuman advance-weather-divining from a sage in Blacksod.

Many of the ‘War’ generation seemed obsessed with the weather forecast, well beyond the point of refusing to acknowledge its shocking deviance. The weather forecast was the most tedious thing on television.

Of course, in Ireland, you couldn’t make plans. Outside of sustained heat waves, no one in Ireland should plan a picnic or barbecue in advance. So you never did. I never cared. I just got on with it.

Operationally, you just had to look at the sky when you got up out of your bed and assume it would last. Equally, in Ireland, there was always a good chance of grey. Like today only greyer. Beyond that it seemed pointless, and unyouthful, to speculate.

But there are other decisions – a snap weekend away, a walk, dependant others to be born in mind, that may depend on an accurate weather forecast – and so with age you find yourself seeking comfort in experts. And when you pay attention you find they nearly always seem to get it wrong.

It’s not that they get it wrong with hurricanes, snowstorms and heatwaves, it’s that they get it wrong – all the time – saying it’s going to shine, or rain, where you’re going to be.

The first thing to notice, even before they get it wrong, is that they smother you with ambiguity, those beguiling, soothing-tongued prognosticators: ‘Sunshine and scattered showers, in the West’. ‘Partly clear becoming cloudy, with a risk of rainspells, in the afternoon’. ‘Fine becoming fair’ It means nothing. Words like ‘should’, ‘possibly’, ‘probably’, ‘may’, ‘likely’, ‘some’ and of course ‘occasional’ compound the cloudiness.

Getting it wrong is the weather forecaster’s speciality. One study found that when television meteorologists in Kansas predicted that there was a 100 percent chance of rain, it didn’t rain at all a third of the time.

On the evening before the worst storm to hit the UK for almost 300 years, the BBC’s well-liked Michael Fish proclaimed on the night of October 15, 1987: “Earlier on today, apparently, a woman rang the BBC and said she heard there was a hurricane on the way. Well, if you’re watching, don’t worry, there isn’t”. There was; and gales at 115mph caused utter devastation across the southern half of the country, leaving 18 people dead, 15 million trees flattened, and damage of £2bn. Though his boss, Bill Giles – the lead forecaster for the station – took the blame for the mistake in 2011, the term “Michael Fish moment” is applied to public forecasts, on any topic, which turn out to be embarrassingly wrong.

On September 29, 2016 the National Hurricane Center in Miami announced that Hurricane Matthew was nothing to worry about just before it exploded into a Category 5 monster that slammed Haiti, killing over 1,000 people before moving on to wreaking 30 mortalities in the US.

In Ireland, during the big freeze of January 2010, Batt O’Keeffe, as minister for education, directed all schools to close for three days, based on a Met Éireann forecast of snow and ice. A thaw immediately kicked in, and he ignominiously rescinded his decision.

Documents released under freedom of information to a few years ago revealed widespread anger at this carry on in Ireland. Typical letters to the Met service were:

“How can Met Eireann get away with wrong forecasts so much, I am baffled? If another service provider got it wrong so much, that service provider would be long gone… Met Eireann says one thing and the sky above our heads says another”.

“What a joke. From forecasting that today would be mostly sunny yesterday to now saying it will be dull and cloudy. This is not forecasting, it’s nowcasting”.

Some years ago Donegal County Council decided to start up its own weather-forecast website because RTÉ was reporting the north-west as a constant wash-out when Donegal had in fact had a scorcher of a summer. However, let’s be clear: the issue of regional bias is a different problem which I don’t want to get into (because it’s ludicrous).

I’m talking here just about inaccuracy.

Last year dodgy councillor and hotel mogul, Donegal’s Sean McEniff, threatened to sue Met Éireann for money lost by cancelled business. He instructed his solicitors to investigate the possibility of legal action against Met Éireann over what he claimed as an inaccurate weather forecast. Sadly he died shortly after the instruction.

The main problem, it seems to me, is that the weather in Ireland is made over the seas, particularly the vast Atlantic ocean but also the Irish sea, and so varies over very small distances. If you live in Germany or Colorado there’s simply less sea to go around and you can see the weather coming. We’re also precariously positioned in a zone of complex transition between warm, moist air (sometimes of tropical origin) moving northwards and colder, denser, drier air (usually of polar origin) which is moving southwards. This is the devious and manipulative ‘polar front’ that ruins so many weekends.

Nevertheless it is claimed, by those concerned only with the facts, that one-day forecasts have an average accuracy within 2 degrees, and that they predict rain (or a lack thereof) correctly 82 percent of the time. That drops to 70 per cent at three days, but even the seven-day forecast has a 50 per cent chance of being accurate. The UK Met Office does a 10-day forecast but – wisely, given its reputation – has ditched its seasonal forecasting which really never amounted to much more than hubris. In April 2009 the Met Office had unwisely issued a press release about the oncoming summer – “barbecue weather”. But it was a washout.

A project at the 2018 Young Scientists Exhibition tended to absolve Met Éireann: two boys from Avondale Community School concluded that: “The forecast gets more accurate as it gets closer to the actual date”. They found “an overall accuracy of 84 to 96 per cent reliability for temperature and wind-speed conditions”. Even more irritatingly the data-crunching kids summed up: “The assumption that the weather forecast is constantly wrong is not supported by our data”.

Technology has improved accuracy: five-day forecasts are nearly as accurate as two-day projections were 30 years ago.

The Fastnet sailing race disaster 40 years ago this August, which cost 19 lives, would not have occurred in the modern era. The tragedy off the southern coast of Ireland was not helped by a flawed – and in effect late – weather forecast caused not by human error but by contemporary forecasting. The weather warning generated by computerised numerical weather predictions systems would have provided strong indications three days before the depression suddenly deepened, touching violent storm force 11 and effecting such devastation.

Hurricane predictions, today, are off by an average of 161km (100 miles), down from 563km (350 miles) 25 years ago. According to ‘the Economist’, “The brute force of ‘petaflop’ supercomputers capable of cranking out 1,000 trillion floating-point calculations per second has helped reduce guesswork…The aim will be to achieve the precision of say, Google Maps, which ‘foretells’ traffic conditions down the road in real-time”. And the European model, managed through facilities like the European Centre for Medium-Range Weather Forecasts in England, is accepted as superior, for example to the US one. It’s run on a more powerful supercomputer. And has a more sophisticated mathematical system to handle the “initial conditions” of the atmosphere. It’s also less centralised.

Admittedly we don’t help ourselves. Forecasters in the US and Europe tend to use percentage models – a location has a particular percentage chance of rain. In Ireland we do it descriptively. It’s easy to quibble respectively with a summation.

Official anger at inaccurate weather reports has a nasty pedigree. Stalin purged meteorologists in 1933 and again in 1946. Earlier this year the man who gets it wrong the most about climate, President Donald Trump, noted “the people that get it wrong the most are the weather forecasters and the political analysts”.

In March 2017 flights to the East coast of the US from Dublin, including one intended to convey Enda Kenny, were cancelled when weather forecasters predicted a winter storm named Stella would drop 18 inches but only 7 inches fell. Chris Christie, then governor of New Jersey, blasted forecasters. “I don’t know how much we should be paying these weather guys”, he said. “I’ve had my fill of the National Weather Service after seven and a half years”.

Ultimately the best defence to weather is not to care. And to dress appropriately. I like my climate unchanging but I’ll take any weather except grey. And even when the weather forecast is wrong it’s not worth talking about. For the young.