Poor visibility presents challenging route finding conditions. Visibility could be significantly less than 50 metres in all directions with few or no visual references, especially on featureless moors or plateaux. Distances become hard to judge and cliff or cornice edges can be difficult to recognise. These conditions require good navigational skills. There is a risk of white-out conditions when mist or fog is combined with extensive snow cover.

Heavy snow can lead to rapid changes in underfoot conditions and paths may become treacherous or hidden. It also brings very poor visibility and often makes navigation much more challenging. When deep snow accumulates progress is often time consuming and strenuous, significantly affecting the distance one can travel on foot. Deep drifts can develop if snow is combined with strong winds. A heightened avalanche risk is possible and avalanche reports should be consulted where available.

Gale force winds (gusts over 50mph) make walking difficult and strenuous with a potential to be blown over by gusts. There is often a marked increase in winds through cols or on exposed ridges and summits. Distances can take longer to cover and compass bearings become harder to follow accurately.

Lightning is a significant mountain hazard which can result in serious injury or death. Mountain terrain often leaves one highly exposed to lightning strikes. Hail may give unpleasant conditions with torrential rain and localised flash flooding also possible, mainly in Summer months.