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Cut-off lows are common features of Mediterranean meteorology in warm months and are often related to severe weather. The present work introduces a classification of cut-off episodes, based on the vertical extension of the depression and the presence of a linked surface vortex, also analyzing precipitation patterns. Ten years of warm-season ERA-40 reanalysis, available every six hours on a 2.5 degrees x 2.5 degrees grid, are processed to extract a database of cut-off lows and surface cyclones, along with the related total and convective precipitation at the ground. The high temporal resolution of the dataset permits a detailed characterization of short lasting events, so far poorly analyzed. The results show the relative abundance (41% of the total) of cut-off events lasting less than 24 hrs, sharing most of the characteristics of longer living cut-off in terms of structures and precipitation pattern. A large part of the 273 events identified in our database, about 54%, appear as high level signatures of depressions extending through a large portion of the troposphere, and in 38% of cases a well defined cyclonic structure is found at the ground. Most of these events carry precipitation, with relatively high rain-rates over wide areas, with well developed frontal rain bands. Among the cut-off events without a deep vertical structure (46%), about half do not produce precipitation, while the others produce relatively high rain-rates, although confined to small areas, indicating the presence of convective systems developing beneath the cut-offlow system. Such precipitation patterns are also confirmed at smaller scales by cloud resolving model runs. Finally, cut-off lows characterized by relatively high potential vorticity values in the mid-upper troposphere seem to have the potential for precipitation

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In the frame of this work, the storm that occurred on 5 December 2002 in Antalya, located on the southwestern Mediterranean Sea coast of Turkey, is analyzed. More than 230 mm of 24-h-accumulated rainfall have been reported during the event that produced floods in the area. The analysis is based on the results of model simulations with the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5). Observational data provided by the Tropical Rainfall Measuring Mission (TRMM) sensors (including the Lightning Imaging Sensor and TRMM Microwave Imager), Special Sensor Microwave Imager (SSM/I), Meteosat-7, and Met Office Arrival Time Difference (ATD) lightning network are used for both the comparison with the model results and also for the characterization of the storm. The synergetic use of all of this information was crucial for the description of the event. The maximum of precipitation was associated with the warm and moist air masses driven by a low-level jet over the area and impinging over the orographic barriers. The improvement of representation of the humidity field in the model initial conditions, through a simple technique of humidity adjustment based on satellite rainfall estimates, resulted in an improvement of the prediction of the timing and quantity of the precipitation maxima during the event.