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This paper comprises a comprehensive account on the outcomes of the 10th Plinius Conference on Mediterranean Storms that was held in Cyprus from 22 to 24 September 2008. Selected papers presented during the Conference were published in two peer reviewed journals that were devoted to this event and are summarized in this concise report.

In the present study, the monthly statistical characteristics of jetlet and tropopause in relation to the development of thunderstorms over Cyprus are examined. For the needs of the study the 12:00 UTC radiosonde data obtained from the Athalassa station (33.4° E, 35.1° N) for an 11-year period, from 1997 till 2007, were employed. On the basis of this dataset, the height and the temperature of the tropopause, as well as the height, wind direction and speed of the jetlet were estimated. Additionally, the days in the above period with observed thunderstorms were selected and the aforementioned characteristics of the jetlet and tropopause were noted. The two data sets were subsequently contrasted in an attempt to identify possible relations between thunderstorm development, on the one hand, and tropopause and jetlet characteristics, on the other hand.

Dynamically induced rainfall is strongly connected with synoptic atmospheric circulation patterns at the upper levels. This study investigates the relationship between days of high precipitation volume events in the eastern Mediterranean and the associated geopotential height patterns at 500 hPa. To reduce the number of different patterns and to simplify the statistical processing, the input days were classified into clusters of synoptic cases having similar characteristics, by utilizing Kohonen Self Organizing Maps (SOM) architecture. Using this architecture, synoptic patterns were grouped into 9, 18, 27 and 36 clusters which were subsequently used in the analysis. The classification performance was tested by applying the method to extreme rainfall events in the eastern Mediterranean. The relationship of the synoptic upper air patterns (500 hPa height) and surface features (heavy rainfall events) was established, while the 36 member classification proved to be the most efficient.

The rainfall and lightning activity associated with three depressions which affected the area of Cyprus were studied in order to identify possible relationships between them. The lightning data were provided by the National Observatory of Athens, Greece, and were spatially and statistically related to the corresponding rainfall measurements from the rain gauge network of the Cyprus Meteorological Service. The study was carried out by using a rectangular grid-box methodology and various combinations of lightning and rainfall data filtering and time-lags were tested.

Flooding is a consequence of the prevailing meteorological situation, the intensity and duration of precipitation, geomorphology, human activities over a geographical region and other factors. Floods result in damage and destruction of infrastructure and private property and, in some cases, in fatalities. Flash floods are sudden and quite localized in extend, characterized by excessive amounts of rainfall within a short period of time and are distinguished from other floods by their degree of severity. The broader knowledge concerning flash floods is useful for the better understanding of the underlying thermodynamic and dynamic mechanisms, as well as the associated physical processes. The wider understanding of flashfloods can form part of an integrated system for short and very short forecasting of these events. In the present study, the synoptic, dynamic and thermodynamic conditions during the development of a baroclinic depression which affected the area of Cyprus on 6 November 2005 are studied. The depression was associated with extreme weather phenomena, such as thunderstorms, a water spout and high precipitation accumulations. The results indicate the importance of the dynamic parameters in the system's development and the thermodynamic analysis has shown the convective potential of the atmosphere.

The contemporary economy of Cyprus is mostly based on services; agriculture was by tradition a strong contributor to the economy of the island, but nowadays its contribution is rather limited. At all times, the agricultural economy suffers from the consequences of weather phenomena such as hail, frost, drought, dust storms, etc. The present study focuses on the impact of hail to the agricultural economy, since hailstorms can straightforwardly destroy crops and plantations. Any knowledge concerning hail is useful for the improved understanding of the underlying thermodynamic and dynamic mechanisms and physical processes associated with its formation. For the investigation of hail as a natural hazard and its contribution to the insurance compensations paid to farmers, hail events and their associated synoptic and dynamic conditions were studied. Hail events were clustered into a "frontal instability hail events" and a "thermal instability hail events" clusters. The spatial distribution of the frequency of hail events was also determined in order to identify geographical areas that are more often hit by hail storms.

Almost every year, localised and in some cases more widespread floodings affect parts of Cyprus, causing damages to properties destruction to infrastructure and housing and sometimes the loss of human life. Various factors such as the meteorological situation and type and intensity of precipitation, the geomorphology, the geology and the human intervention to geomorphology are responsible for flood events. In the present study, only the meteorological situation and the associated mechanisms are examined in an attempt to gain the essential knowledge for improvement of local weather forecasts. The study period covers a thirteen-year period, from 1994 to 2006, in which 43 cases of flooding were reported, mainly over urbanized areas. The dominant favorable weather conditions for flood events are either the existence of a depression or weather conditions of convectional type. According to these two factors, the flood events were classified into two categories; the "instability'' category which includes isolated flood events of short duration, and the "depression'' category which includes widespread flood events of long duration.

Hail is a hazardous weather element often accompanying a thunderstorm, as a result of either thermal instability or instability associated with baroclinic synoptic-scale systems (i.e. frontal depressions). Nevertheless, instability of any kind and thunderstorm activity does not always lead to the formation of hail of adequate size to reach the ground. The broader the knowledge concerning hail events the better the understanding of the underlying thermodynamic and dynamic mechanisms, as well as the physical processes associated with its formation. In the present study, the severe hail events that were recorded in Cyprus during the ten-year period from 1996 until 2005 were examined, first by grouping them into two clusters, namely, the "thermal instability cluster" and the "frontal depression cluster". Subsequently, the spatial and temporal evolution of the synoptic, dynamic and thermodynamic characteristics of these hail events was studied in depth. Also, the impact of hailstorms on the local economy of the island is presented in terms of the compensations paid by the Agricultural Insurance Organization of the country.

The synoptic, dynamic, energetic and thermodynamic conditions during the development of a baroclinic depression which affected the area of Cyprus from 5 to 9 February 2006 are studied. The depression was associated with extreme weather phenomena such as thunderstorms, strong winds, dust and high precipitation accumulations (amounting to 50% of the mean monthly value). The results underline the importance of the dynamic control on the cyclone's development and the important contribution of the system itself in the energetics of the atmosphere. The thermodynamic analysis has proved a very useful tool in identifying the convective potential of the atmosphere at various stages of the development.

Weather radars are used to measure the electromagnetic radiation backscattered by cloud raindrops. Clouds that backscatter more electromagnetic radiation consist of larger droplets of rain and therefore they produce more rain. The idea is to estimate rain rate by using weather radar as an alternative to rain-gauges measuring rainfall on the ground. In an experiment during two days in June and August 1997 over the Italian-Swiss Alps, data from weather radar and surrounding rain-gauges were collected at the same time. The statistical KNN and the neural SOM classifiers were implemented for the classification task using the radar data as input and the rain-gauge measurements as output. The proposed system managed to identify matching pattern waveforms and the rainfall rate on the ground was estimated based on the radar reflectivities with a satisfactory error rate, outperforming the traditional Z/R relationship. It is anticipated that more data, representing a variety of possible meteorological conditions, will lead to improved results. The results in this work show that an estimation of rain rate based on weather radar measurements treated with statistical and neural classifiers is possible.

A comparison is made between the precipitation forecasts by the non-hydrostatic limited area model LME of the German Weather Service (DWD) and observations from a network of rain gauges in Cyprus. This is a first attempt to carry out a preliminary verification and evaluation of the LME precipitation forecasts over the area of Cyprus. For the verification, model forecasts and observations were used covering an eleven month period, from 1/2/2005 till 31/12/2005. The observations were made by three Automatic Weather Observing Systems (AWOS) located at Larnaka and Paphos airports and at Athalassa synoptic station, as well as at 6, 6 and 8 rain gauges within a radius of about 30 km around these stations, respectively. The observations were compared with the model outputs, separately for each of the three forecast days. The "probability of detection" (POD) of a precipitation event and the "false alarm rate" (FAR) were calculated. From the selected cases of the forecast precipitation events, the average forecast precipitation amounts in the area around the three stations were compared with the measured ones. An attempt was also made to evaluate the model's skill in predicting the spatial distribution of precipitation and, in this respect, the geographical position of the maximum forecast precipitation amount was contrasted to the position of the corresponding observed maximum. Maps with monthly precipitation totals observed by a local network of 150 rain gauges were compared with the corresponding forecast precipitation maps.

no abstract available.