In Apple's own weather forecast, there is a kind of weather that is winding and linear. What does this mean?

That curve represents the breezy weather in the weather forecast.

Common symbols are as follows:

Cloud symbols: Cirrus, cirrocumulus, cirrostratus, Cumulus, nimbostratus, Cumulonimbus, etc.

Clouds with white spots indicate: blizzard, snowstorm, etc.

Blue point cloud indicates: continuous heavy rain, light snow and light showers.

Cloud plus lightning means: thunderstorm, lightning, etc.

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.

Baidu encyclopedia-weather forecast