Interannual variability of cut-off low systems over the European sector: The role of blocking and the Northern Hemisphere circulation modes

Impact of Euro-Atlantic blocking patterns in Iberia precipitation using a novel high resolution dataset

“…Trigo et al (2004) found that blocking episodes 74 in the Euro-Atlantic sector reduce the precipitation rate at higher latitudes, and increase it in southernmost 75 areas of Europe. In addition, blocking can be favorable for strangling upper level cold air pools (usually 76 referred as cut-off lows), which may produce severe weather and flooding (Nieto et al, 2007). Cut-off 77 lows are more frequent in spring and summer seasons, and in mid and low latitudes, with the European 78 sector being a preferred sector of occurrence.…”

“…Cut-off 77 lows are more frequent in spring and summer seasons, and in mid and low latitudes, with the European 78 sector being a preferred sector of occurrence. In particular, Nieto et al (2007) has shown that the southern 79 flank of blocking systems is a favorable location for cut-off occurrence. This is crucial for the climate of …”

Extreme Precipitation Events in Summer in the Iberian Peninsula and Its Relationship With Atmospheric Rivers

“…This dichotomy is mainly due to thermodynamic effects and to dynamical processes associated with the intra-annual variability of precipitation in the IP. In the transition months of April, May, and September the dynamical processes over the North Atlantic Ocean and the Mediterranean play an important role, with the months of April and May associated to the still active storm track (Trigo, 2006) and high frequency of Cut-off low systems (Nieto et al, 2007). September extreme events are fueled by very high values of SST in the Mediterranean, often associated with the developing of MSC (García-Herrera et al, 2005).…”

“…In addition, due to the warming in the interior region of the IP there is often the generation of a thermal depression that can be associated to localize convective precipitation (Hoinka and de Castro, 2003). In the transition months (April, May, and September) the atmosphere is very unstable due to the presence of extra tropical cyclones and their associated frontal systems (Trigo, 2006) but also to the developing of cut-off lows (Nieto et al, 2007), causing the existence of precipitation. The Mediterranean will also have an influence on the precipitation in the IP in particular on the coast adjacent to the Mediterranean where positive anomalies of sea surface temperature often associated with the developing of Mesoscale Convective Systems (MCS) are known for producing extreme precipitation (García-Herrera et al, 2005).…”

Contribution of large-scale midlatitude disturbances to hourly precipitation extremes in the United States

“…By contrast, cutoff lows (COL) occur when midlatitude wave energy extends equatorward of the jet during an amplified flow regime and ultimately become displaced from midlatitude flow [e.g., Nieto et al (2007)]. Recent studies have shown that COL contribute to a substantial portion of annual precipitation and multi-day precipitation extremes across parts of the globe (Favre et al 2013) including the US (Abatzoglou 2016).…”