For lots of locations, it might seem quite obvious what the weather will be like. However, this just isn’t always the case. Weather conditions can vary greatly between different locations, even if they are quite close together or have a reputation for their weather being a certain way.
Even locations that are close to the UK can have drastically different weather. For example, if you are planning a winter break to Poland or Germany, depending on where you are going, it could be incredibly cold. You should pack for severe weather conditions and the distinct possibility of snow, rather than the milder winters that tend to occur in the UK.
If you are going to somewhere like Asia, it will have a reputation for being warm all year round. You must do your research though because whilst it might be warm, it will not necessarily be dry. Different areas have their monsoon seasons and rainy seasons so do your research first.