Taking the weather with you

30/07/2010

We look at why it’s so hard to get weather predictions right, the worst forecasting fails and home gadgets to see if you can do better than the experts

Weather forecasting isn’t an exact science; some forecasters have even fessed up to it being an educated guess.  It is the application of science and gadgets to predict the state of the atmosphere for a future time and location…when you put it like that it does sound tough.

Modern forecasts are made by meteorologists collecting quantitative data about the present atmosphere then using their knowledge of science relating to atmospheric processes to predict how the atmosphere will evolve. 

But there is still a large chance for human input, or error.  Meteorologists must pick the best forecast model for the prediction which involves recognising complex patterns and knowledge of how the model has performed previously, plus model biases. 

Taking into account this tricky process  plus the chaotic nature of the atmosphere, massive computers that solve the equations, the error involved in measuring the conditions of the weather, and dubious understanding of all the atmospheric processes, we might go a little easier on the weather girl/boy next time they slip up!

Forecasts also become even less accurate the further ahead they are made as there is more time for the atmosphere to change.

Forecast fails

Heat waves have been predicted when a miserable summer awaited, hurricanes have failed to materialise but hit elsewhere with devastating effects and farmers’ crops have been ruined when rainy days failed to live up to expectations.  However, the great storm of 1987 dominates all mis-made weather predictions…although maybe it wasn’t so wrong after all!

BBC weatherman Michael Fish’s successful career was plagued by the apparent dismissal of a major storm which swept over south east England in 1987.

The now infamous quote goes: “Earlier on today apparently a lady rang the BBC and said she heard that there was a hurricane on the way. Well don’t worry if you’re watching, there isn’t.”

Of course there was. It turns out Met office forecasters were warning of severe weather four days before the storm hit, but their data suggested it might pass over the English Channel, skipping the UK mainland.  Consequently, no warnings of extreme winds were made on the evening weather forecast the night of the storm.

At its peak, storm winds measured 117knots (that’s v windy) in Normandy with winds of 70knots keep up their power for about four hours.  Bizarrely the temperature also soared in Hampshire by almost 9 degrees.

Fish maintains his oft-quoted forecast as referring to a storm in Florida which was in the news…not the UK weather.  In his full clip he broadcast: “batten down the hatches, there’s some really storm weather on the way,” but that is usually cut short for dramatic effect!

Prediction gadgets

No, we’re not talking crystal balls. There are any number of home weather forecast gadgets from the extremely pricey to cheap and chic.  Often highly functional, or ugly with dials, Oregon Scientific has made sleek digital weather stations for the modern home with different coloured lights alerting owners whether they’ll need sun cream tomorrow or a brolly.

Microsoft and Google have both got weather widgets you can add to your PC’s desktop, while there are a plethora of weather apps for phones.

 If you want to go back to nature you could invest in some old school anemometers, wind vanes, water gauges and the like but you might need a weather jargon buster to fathom out the what’s and whys.

Given the unpredictable nature of the weather, some people prefer to eschew gadgets all together and resort to more traditional production methods. 

Check out pine cones next time you’re out- they are said to open and close according to the humidity of the air, so an open cone will mean dry weather and a closed one a miserable day indoors.

Superstitious Brits also maintain you can spot a scorching summer from oak and ash trees.  If the ash grows leaves first, we’re in for a rainy time, but if the oak leaves beat the ash to it, fire up the BBQ!

The rhyme goes like so: ‘Ash leaf before the oak, then we shall have a summer soak; Oak leaf before the ash, the summer comes with nary a splash.’

Do they work, who knows.  If you’re psychic or have any weather prediction tips, let us know!