How does the weather forecast predict the weather?

Weather forecasting is the use of modern science and technology to predict the state of the earth's atmosphere at a certain location in the future. Since prehistoric times, humans have begun to predict the weather to arrange their work and life accordingly (such as agricultural production, military operations, etc.). Today's weather forecasting is primarily based on collecting large amounts of data (temperature, humidity, wind direction and speed, pressure, etc.) and then using current knowledge of atmospheric processes (meteorology) to determine future air changes. Due to the chaos of atmospheric processes and the fact that today's science does not finally have a thorough understanding of them, weather forecasts will always have a certain amount of error.

What CCTV broadcasts at 19:30 every night is short-term weather forecast, which is valid for the next 2 to 3 days.

Extended information

Weather forecasting by ancient Chinese:

For thousands of years, sailors, fishermen, farmers and hunters have watched clouds, wind, and celestial phenomena. Predict the weather by looking at objects and explore weather forecasting. Weather forecasting became a folk art. Ancient people observed celestial phenomena and measured wind and clouds. The former is a sky condition that can be observed with the naked eye and simple instruments. It not only observes the changes of the sun, moon and stars, but also records various past and current natural phenomena, and combines the summarized experience with current observations to make weather forecasts.

Reference weather forecast - Baidu Encyclopedia