What is the meaning of the present weather group '-RASN'?

The present weather group '-RASN' indicates conditions of light rain and snow, often accompanied by mist. The "-R" signifies light rain, while "ASN" refers to the occurrence of both rain and snow, where "SN" specifically denotes snow. In this context, the notation indicates that the precipitation is predominantly light in intensity. The use of the minus symbol before the weather group also reinforces the idea that the overall intensity of the weather conditions is light.

In aviation weather reporting, this type of shorthand is crucial for quickly conveying important information to pilots regarding current weather phenomena, particularly those that may affect visibility and flight operations. Understanding this abbreviation helps in interpreting weather reports effectively, keeping in mind that the presence of mist could also imply reduced visibility.