How accurate is the weather forecast?
This is a hard question to answer. The reason is, because while the forecast is usually pretty accurate in general over a wide area, locally it can be way off. Many weather phenomena are local for instance rain squalls or thunderstorms. Sometimes they affect an area only about twenty miles wide or less. If the forecast was for clear weather over four states and one or two small areas have heavy rain squalls, to those people it seems the weather forecaster has really blown it.
Britain’s Meteorlogical Office claims an 86 % accuracy for it’s 24 hour forecasts. 5 day forecasts are at 80 % accuracy. Why aren’t they more accurate? Well, weather systems are extremely complex. It is simply not possible to take into account all of the factors necessary to provide a foolproof forecast. And scientists still don’t fully understand all of the forces of nature that shape the weather. Despite this, however, modern weather forecasting gets it right most of the time. So, it still pays to check out the forecast before heading off for a day in the sun.