In this study we analyzed the annual and seasonal variability of snowfall events in the Spanish Pyrenees, and the relationship between different weather types and normal (between P30 and P80) and intense (> P80) snowfall events. Data for the hydrological years 2008-2013 were obtained from 10 telenivometers (TNMs) managed by the ERHIN Program network. The TNMs were classified and clustered using principal component analysis (PCA) and k-means classification procedures.The results indicated that

more »

... ere was significant variability in annual snow depth amongst both TNMs and years, with the eastern TNMs showing the most inter-annual variability. The western TNMs recorded most annual accumulation in the winter months (December, January, February), whereas those located eastward showed more homogenous accumulation over winter, spring, and late autumn. Analysis of the frequency and intensity of snowfall did not show clear spatial patterns. No relationship was found between geographical variables (elevation, longitude, latitude) and the frequency of snowfall greater than 5 cm. However, a relationship between longitude and snowfall greater than 25 cm was found, showing that western areas are more likely to receive heavy snowfall. Snowfall of medium intensity (P30-P80) was associated with weather types from the northwest, north, and west, while for heavy snowfall events (> P80) the dominant types were from the northwest, followed by the north, and to a lesser extent the west. The western TNMs recorded that Atlantic Ocean weather types brought the most frequent snowfall, while the eastern TNMs showed that Mediterranean weather types were more important.This study indicates that snowfall differs among Pyrenean valleys, with weather types responsible for much of the variability, particularly with respect to normal and extraordinary snowfall events. However, the elevation of the TNMs may have had an effect, necessitating further research to enable quantification of the effects of snowfall gradients in the Pyrenees.