Of course we make a sacrifice to the weather spirits every evening before a trip, but nevertheless the Scottish weather can be surprisingly fierce (that’s why we go there).  For every 300m (1,000ft) you ascend the temperature drops by roughly 1⁰C (2⁰F).  Add wind chill and we’re talking around -20⁰C.  Pay attention to your jacket, boots, gloves and sleeping bag, the quality of these items will have the greatest impact on your comfort and wellbeing.