I borrowed a Pocket Weather Station to try it out this weekend but
unfortunately there was'nt a lot of weather about, and certainly not much wind.
The product claims to give wind speed, temperature, pressure, humidity and altitude. The barometer has a memory to show if the weather is likely to improve or worsen, and a 'storm imminent' alarm if the pressure drops very rapidly. Sounds good……
Without the weather to measure. I wondered what a professional forecaster would make of such a device. I then decided to have another look at Frank Singleton's 'Weather for Sailors' website www.franksingleton.clara.net Frank is a recent winner of a RYA Community Award for services to sailing. His speciality is weather forecasting as his biographic details show: He spent his working life in the Met Office working in various departments including Research, Forecasting, Applied Climatological Services and Personnel. In mid-career he was a Senior Forecaster at Bracknell with overall responsibility, among many functions, for the Shipping Forecast. His final post was as Divisional Director in charge of Observing.
As luck would have it Frank has made some comments re the value of such devices. Some edited comments follow: “As a young lad, beginning to take an interest in the weather, a well meaning friend gave me a "forecasting" gismo. This was of plastic, in the form of concentric discs. These were rotated to align wind direction and barometric tendency (rising, falling and rate of change). A forecast could then be read off. Similar gadgets are available today. Several firms now market recording barometers, very useful in themselves, but with the same ideas built into the software. But are such forecasting methods of any value?”
The Limitations of Single Observer Forecasting
The Head of the UK National Met Centre (Central Forecast Office) said recently -
"In order to be able to forecast anywhere, you have to able to forecast everywhere."
Frank's comments: “What he is saying is that the atmosphere is a complex machine and that what happens at any one place is a result, to a greater or lesser extent, of what is happening everywhere else. That is not to say that experience should be ignored any more than a rapidly rising or falling barometer. However, it is worth noting that to be able to forecast on a regular basis for -
A few minutes ahead needs information within your vicinity.
A few hours ahead needs information from an area comparable to the British Isles.
One day ahead needs information from most of the North Atlantic, the Eastern USA and much of Europe.
Several days ahead needs knowledge of global weather.
Clearly, none of these questions can be answered from the single observation of the pressure, wind and cloud.
What can you do at sea?
The moral is - watch your barometer, observe changes in wind and cloud, try to understand why they are changing. Are these just diurnal effects such as the sea breeze or something bigger? BUT - ignore at your peril the National Weather Service forecasts produced by professionals using the most powerful computers and the most advanced theories capable of being handled by the hardware. They may not be accurate, but they will usually be useful. Use your observations and your experience to help monitor the weather and the forecast.
It follows from what I have said above that those little gismos that claim to predict weather instantly are no more than a bit of fun. Their only practical use is as recording barometers. I do have one of those on board that lets me see hourly readings of pressure over the past 24 hours”.
For the complete article visit Franks website which can be found at: www.franksingleton.clara.net
