The weather situation evolves from an existing situation following specific physical laws. Weather forecasts are based upon a series of measurements of the atmosphere which are taken at a specific moment in time, and which define the existing situation.

These measurements which are taken on the surface of the earth weather stations, at altitude (weather balloons), and in space (satellites) are matched to models from which is then calculated the evolution of each of the parameters.

Why is it that often forecasts appear to be wrong?
If small phenomena have been ignored or not given sufficient importance in the initial calculations it can, on occasion, cause wide variations between the forecast and reality situation.

A drop in barometric pressure that is greater than forecasted, or a difference of more than I0 knots between the forecast and the actual wind speed should alert you.

In brief
It is the duty of Marinecall to provide you with the best information possible. It is your responsibility to be observant and to monitor the evolving weather situation.

At all times you must remain vigilant!