What does "-"mean in the weather forecast?

The meaning of the weather forecast symbol on Apple's mobile phone is as follows:

The main contents of weather forecast are the future rain, maximum and minimum temperature, wind direction and wind force and special disastrous weather in a region or city. As far as China is concerned, meteorological stations accurately predict the location and intensity of natural disasters such as cold wave, typhoon and rainstorm.

Extended data

Each symbol represents a particular weather. The symbols representing clouds are Cirrus, cirrocumulus, cirrostratus, Altocumulus, nimbostratus, Cumulonimbus and so on. Symbols representing weather phenomena include: thunderstorm, tornado, fog, continuous heavy rain, light snow and light showers. In addition, there are symbols indicating the change of wind direction, wind speed, cloud cover and air pressure.

All these symbols are filled in their respective geographical positions in a unified format. In this way, meteorological elements such as wind, temperature, humidity, air pressure, clouds, cloudy, sunny, rain and snow observed at the same time in a wide area can be filled in a weather map. So as to form weather maps representing different times.

References:

Baidu Encyclopedia: Weather Forecast