Precipitation

Nationally, Krkonoše features the greatest activity as regard precipitation, this increasing with altitude. Solid forms of precipitation, i.e. snow, hail and ice, prevail in the higher locations over rainfall in terms of the yearly total. At the foot of the range, annual precipitation is about 800 mm, whilst the ridges receive 1,200–1,400 mm. However, even greater figures can be measured in the valleys, e.g. Špindlerův Mlýn gets up to 1,322 mm and Pec pod Sněžkou even 1,405 mm of precipitation annually. Most places in the Krkonoše Mountains show the highest totals in August as a result of the flow of westerly winds and numerous thunderstorms, while the lowest volumes occur in the spring (a minimum being recorded in March), which with regard to the amount of snow and plentiful meltwater is difficult to comprehend in reality. When it comes to annual totals, they vary greatly year on year.

Rarely there are also cases of rainfall at natural disaster levels, these effectively causing waves of water arising through storm and flood; landslides are also common (debris avalanches). Such circumstances may in some places produce l00–200 mm or even more rainfall per day (for instance, 240 mm, which is the average total for 2 months, in Obří důl and the area of Sněžka as recorded on 29 July l897).