Why is the weather forecast inaccurate? Why does it not snow in Beijing?

On the streets of Beijing on the 20th, everything was the same as yesterday. Not only was there no "medium snow" in the forecast, but even sporadic light snow was not seen.

Guo Hu, director of the Beijing Meteorological Observatory, said in an interview that Beijing failed to snow as scheduled on the 20th because the intersection of cold and warm air was "displaced", which was several tens of kilometers south than expected. "It is snowing everywhere in Shijiazhuang. In layman's terms, it is like meeting in front of the princess's grave, but it is temporarily changed into a space bridge. " "19 night, the cold air suddenly became stronger in the process of going south, and the moving speed accelerated, completely controlling the sky over Beijing, and moving the warm and humid airflow out of the boundary of Beijing at the expected speed." Guo Hu said that the intersection of cold and warm air flow has thus "shifted" to Shijiazhuang and Shanxi in southern Beijing and central Hebei, where it snowed from the night of 19 to the day of the 20th.

"There is a big error in the prediction, and we are very sorry, because although the accuracy of the prediction is not 100%, we did make an effort of 100%." Guo Hu said that as a forecasting discipline, weather forecasting, like other forecasting disciplines, also has uncertainties, so the forecast cannot be completely consistent with the actual weather conditions, and it is very difficult to forecast with an error of several tens of kilometers like today.