Atmospheric Rivers (ARs) &ndash; long and narrow structures of anomalously high water vapor flux located in the warm sector of extratropical cyclones &ndash; have been shown to be closely related to extreme precipitation and flooding. This paper analyzes the connection between ARs and floods in the Spanish region of Galicia under different synoptic conditions represented by the so-called <q>weather types</q>, a classification of daily sea level pressure patterns obtained by means of a simple scheme that adopts the subjective procedure of Lamb. Flood events are identified from oficial reports of the Spanish Emergency Agency from 1979 to 2010. Results suggest that although most flood events in Galicia do not coincide with the presence of an overhead atmospheric river, the latter are present in the majority of severe cases, particularly in coastal areas. Flood events associated with ARs are connected to cyclonic weather types with west and southwesterly flow and occur mostly in winter months. The link between ARs and severe flooding is not so apparent in inland areas or summer months, in which cases heavy precipitation is usually not of frontal nature but convective. Nevertheless, our results show that, in general, the amount of precipitation in flood events in Galicia more than doubles when an AR is present.
Eiras-Barca, J., Lorenzo, N., Taboada, J., Robles, A., & Miguez-Macho, G. (2017). On the Relationship Between Atmospheric Rivers, Weather Types and Floods in Galicia (NW Spain). Natural Hazards and Earth System Sciences Discussions, 1–16. https://doi.org/10.5194/nhess-2017-145