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The Global atmospheric Electric Circuit (GEC) sustains the fair weather (FW) electric field, or potential gradient (PG). In this article, we analyze PG measurements recorded between 2017 and 2021 at the Instituto de Investigaciones Científicas y Técnicas para la Defensa (CITEDEF) in Buenos Aires, Argentina, to calculate the daily PG (FW) curve and examine whether local PG measurements capture the GEC signal. With the aim of supporting future common methodologies that do not rely on meteorological data for FW identification - and hence aid inter-comparisons, we rely on previously developed statistical methodologies to propose a FW selection based on the absolute deviation from the median of the data series. Using this methodology we filtered FW days and showed that the local PG (FW) curve had a significant correlation of 0.83 with the Carnegie curve. In order to test the extent to which the local daily PG (FW) curve captures the global thunderstorm signal, the area of thunderstorms was calculated at both global and regional scales using data from the Thunder Hour Database (http://thunderhours.earthnetworks.com). The PG (FW) curve was shown to have a good correlation with the daily median variation of the global thunderstorm area on both annual and quarterly scales. Additionally, the analysis of coincident aerosol optical thickness (AOD) measurements by the AERONET network and temperature observations helped to conclude that local effects such as pollution from a near highway are not dominating the PG (FW) curve behaviour. Both analyses allowed us to conclude that the GEC signal can be detected in Buenos Aires. [Display omitted] • The daily PG curve (FW) in Buenos Aires has a correlation of 0.83 with the Carnegie curve with 95% confidence. • The daily PG (FW) curve in Buenos Aires has a seasonal variation that accompanies the global changes of thunderstorm areas. • Local effects such as pollution from a near highway are not dominating the PG (FW) curve behaviour. [ABSTRACT FROM AUTHOR]

• This work presents the longest radar-based climatology of supercells storms using weather radar data in central Argentina. • Predominance of cyclonic supercells (a ratio of 90 • The characteristics of the pre-convective environments associated with supercells in Paraná have yielded similarities to Córdoba region (Argentina). • The Storm Relative Helicity deficit in the 0–1 and 0–3 km layers generates the greatest differences between the pre-convective environments associated with supercells between central and Eastern Argentina and U.S. Great Plains. • The previous point suggests the need to adapt the thresholds of those environmental parameters that particularly depend on the helicity relative to the storm in central-eastern Argentina if they are to be used for forecasting purposes in this region. Some of the strongest storms on Earth occur over central-eastern Argentina. These storms are associated with severe weather phenomena such as big hail, heavy rain, intense wind gusts, and, occasionally, tornadoes. The relatively recent expansion of the radar network in this area brings the chance to better characterize severe weather storms. This study presents a nine-year climatology of supercells (SCs) and their associated mesocyclones (MCs) based on radar data over central Argentina, together with a preliminary analysis of the thermodynamic environment in which they develop. We propose an MC detection algorithm based on the Non-Maximum Suppression (NMS) technique and a subjective classification. The MCs have shown a mean lifetime of 73 min, with their maximum intensity located at 4.7 km above ground level (AGL) on average. The monthly frequency of SCs in central-eastern Argentina is similar to that reported in previous studies near the Sierras de Córdoba, with two relative maxima, one in November and the other one in February, and with an absolute minimum in June. The diurnal cycle shows an absolute maximum at around 0100 UTC (2200 local time) and a minimum between 0900 and 1500 UTC (0600 and 1200 local time). Based on the results obtained here, the pre-convective environments associated with SCs in the Paraná region are very similar to its analogs in the Sierras de Córdoba. They are characterized by high values of convective instability and vertical wind shear. Storm relative helicity (in the low and middle layers) and wind shear in the first kilometer above the surface are lower than those found in the U.S. Great Plains. Although the analysis shows that there are environmental parameters that can discriminate well between SC and non-SC events, their values are shown to be far from the thresholds considered in the U.S. Results hence suggest the need to adapt the thresholds of some of the parameters studied here, particularly those based on storm-relative helicity, to central-eastern Argentina. [ABSTRACT FROM AUTHOR]