Summer precipitation in the mountains of the Picos de Europa of northern Spain

This study investigates the altitudinal distribution of summer precipitation in the mountains of the Picos de Europa of northern Spain. Measurements made during 1984 and 1985 show chat precipitation occurs under two sets of synoptic conditions. Precipitation is either associated with onshore moist airstreams or with the passage of cold fronts cross the region. Under the former conditions, a significant proportion of precipitation is in the form of fog, and precipitation totals appear co be at a maximum close to the altitude o f the cloud base. Under the latter conditions, precipitation displays a far more complex relationship with altitude. These results suggest chat earlier efforts to calculate the water budget of the region by extrapolation of observations of precipitation make at lower altitude may not be reliable and may only provide a partial picture of the complexities of precipitation in the mountains.