To the Comparison between Numerical Methods and Methods Now in Use for Forecasting Meteorological Charts

Methods now in common use for making prognostic charts to a large extent are based on time derivatives, while the numerical methods start from space derivatives. That is the fundamental difference between them. It is shown that the present methods give at times very good results, and that the degree of success varies with the weather situation, characterized e. g. by the average interdiurnal pressure change over the test area. Because of this variation it would be desirable that every test of a numerical method includes a comparison with results obtained at some forecasting center or, at least, with the results of pure extrapolation.