Numerical weather prediction—or numerical forecasting—is the science that believes that weather forecasting is possible if one has a thorough knowledge of the laws of physics and also knows the current state of the weather. Proposed by a group of Norwegian scientists collectively known as the Bergen School, the idea was that air behaves much like a fluid, and that it therefore adheres to the hydrodynamical equations that liquids like water do. Knowing the current state of the weather is vital, and so numerical forecasting relies heavily on having detailed weather reports from multiple locations before predictions can be made. Once this is available, mathematical formulas are applied to the weather’s current state based on the principles of thermodynamics, the Boyle’s law, Newtonian physics, and so on.