It is not only inefficient to use the raw time series of meteorological parameter such as temperature refractive index structure parameter, wind speed and temperature to make short-term prediction, query similarity and classify and cluster time series, but also affects accuracy and reliability of data mining of time series. This article proposes a simple and fast method which based on the election of extrema point and tendency turning point to make the piecewise linear representation of time series. The method can extract the main pattern of series effectively, and reduce the dependency of threshold. It has the characteristic of small cost of computing, efficient and convenient and strong commonality. Then based on that, the experiments on temperature refractive index structure parameter and other kinds of meteorological parameter are implemented and conduct the comparison analysis between the method and another kind of sequence segmentation algorithm. The result shows that the method proposed is capable of reflecting the pattern of time series effectively and accurately.