Ski jackets are waterproof by their nature - they have to be to operate in snow and powder. However, waterproof is a linear measure, not an absolute term. Waterproofing is measured in millimetres, representing the height of a column of water 1-inch wide that can be poured onto the garment without water ingress (static column water resistance test). So the higher the number, the more waterproof performance you can expect. Here is a quick breakdown of levels of waterproofing :-


A waterproof ski jacket is only useful to you if it is breathable too. Water vapour and sweat need to escape, so a decent level of breathability is recommended. This is especially true if you are a more advance skier and will be working hard in mogul fields or off-piste powder.

Breathability is generally measured by the formula g/m²/24h - meaning the grams of water passing through a square meter of fabric in 24 hours. This is also often expressed as MVP (moisture vapour perspiration) but it is the same measurement. So higher ratings mean they are more breathable ski jackets.

Unfortunately the is no universally excepted testing regime for rating breathability, so comparing manufacturers ratings can be less than fruitful. However, do gauge ski jackets against each other from the same brand as they will have undergone the same testing criteria within the brand’s testing laboratories. Here is a quick indicative scale of breathability :-