The upcoming weather is important to many people for a myriad of reasons. The governments set up weather stations all over the world to observe and record weather on a daily basis. The ships at sea carry weather instruments to aid in gathering at the same time. The gathered information is then sent to other weather stations. Computers are used for rapid preparation of maps and charts. Weather information is recorded using symbols. (See diagram #1)
After weather data has been collected, meteorologists draw lines between weather stations reporting the same barometric pressure. Lines indicating equal pressure are the isobars. They also do the same for stations with equal temperatures. Theses lines are called isotherms. Isobars help locate the high and low pressure areas. Isotherms help to locate warm and cold air masses.
It is through the studying and comparing of maps showing cold and warm fronts, highs and lows over several days that weathermen can predict weather. Weather can be predicted from the past direction with the speed of highs and lows the kind of weather in different localities can expect.
In order for the meteorologist to predict weather, he must find the air masses, identify them, discover how fast and in what direction they are moving. Because of the size of masses, it requires many weather stations all over the world working together in tracking them down. Weather data is sent daily to the three world Weather Centers; Suitland, Maryland, USA; Moscow, USSR, (before the split) and at Brisbane, Australia.
Forecasting is based on knowledge and there is never enough information available to be absolutely sure about what the weather is going to do next. Weather forecasting for the next few hours are normally very good, but if made for 2 or 3 days ahead they are less likely to be accurate. General forecasts about the likely-hood of weather does not give precise details. They are based on studies made from past conditions.