What are the grades of precipitation in the weather forecast?

The precipitation level given by the weather forecast is:

The 24-hour precipitation forecast grade * * * is divided into 12 grade, and different grades of precipitation respectively correspond to a certain amount of precipitation, among which sporadic rain and Mao Mao rain refer to the precipitation below 0. 1mm within 24 hours, while light rain, showers and thunderstorms refer to the precipitation below 0. 1 ~ 9.9mm within 24 hours, and so on. Moderate rain corresponds to 10.0 ~ 24.9 mm, moderate rain corresponds to 17.0 ~ 37.9 mm, heavy rain corresponds to 25.0 ~ 49.9 mm, heavy rain corresponds to 38.0 ~ 74.9 mm, heavy rain corresponds to 50.0 ~ 99.9 mm and heavy rain corresponds to 75.0 ~ 6544.

It is not difficult to find that the precipitation in the same 24 hours is 0. 1 ~ 9.9 mm, which can be expressed in three different ways: light rain, shower and thunderstorm, which mainly depends on the nature of precipitation. In addition, the precipitation grade is not the precipitation rate. So if it rains 25 mm evenly within 24 hours, the weather forecast will say it is a rainstorm. However, if there is only 20 mm of heavy precipitation in a certain 1 ~ 2 hours within 24 hours, even if it rains heavily, it is only moderate rain.

Another interesting problem is that the 24-hour precipitation has a special time as the meteorological boundary: 20: 00 every day to 20: 00 the next day is a meteorological precipitation day. Therefore, if there will be 50 mm precipitation from this afternoon to tomorrow morning, but the 50 mm precipitation will be divided into two parts by 20: 00, then the daily precipitation predicted by the weather will not release heavy rain. However, as the forecast description of the whole precipitation process, in the external service, the precipitation from afternoon to tomorrow can be considered together, and the rainstorm forecast can be released at this time.