We normally talk about the weather on a particular day in the terms of things that matter to us, such as rain or snow, warmth or cold, windiness or calm.
If we talk about the average weather for a time of year we normally use numbers for this (and we say things like "the average for the time of year is ..."). The pattern of weather is called climate.
Weather is a major topic, so find out about each feature, such as rain, fronts, hurricanes, snow and so on using their names.