# Spatio-Temporal Distribution of Deep Convection Observed along the Trans-Mexican Volcanic Belt
## 1 Introduction  
Clouds play a key role in global climate regulation. Their interaction with large-scale atmospheric circulations primarily results from three processes: phase changes, radiative transfer and the turbulent transport of air parcels [1]. The study of these cloud feedbacks is essential to gain a better understanding of the association between atmospheric circulations and the cloudiness that characterizes the weather regimes [2]. It is also necessary for the correct parameterization of clouds in general circulation models (GCMs) [3, 4, 5]. Within the extensive diversity of clouds, those associated with strong vertical growth (i.e., towering cumulus/cumulomibus) are of particular interest. In addition to their impact on atmospheric dynamic and thermodynamic processes, even towards climate scales (e.g., [6]), they may also affect their local environment in a socio-economic way. These kinds of deep convective clouds (DCCs) can develop into severe storms with associated severe weather patterns such as lightning, large hail, heavy rainfall leading to flash flooding,strong winds and even tornadoes, which in turn may have significant socio-economic impacts; for example, in the aviation industry (icing, downbursts) the agricultural sector (bad crops) and the insurance industry (damage due to storms). In this sense, [PERSON] [7] reports, for the period 1980-2014, that 41% of loss events, property damage and bodily injuries worldwide are related to meteorological causes (including convective and local storms). These kinds of events also represent 25% of fatalities and 71% of insured losses. Weather-related disasters around the globe also show a positive trend in occurrence and damage [7]. In Europe, a similar trend for tornadoes, violent winds, flash floods and large hail is observed [8]. Likewise, in Mexico and Central America, weather-related disasters represent the largest percentage of the total societal impacts associated with natural hazards [9]. The link between severe storms, associated severe weather and deep moist convection is well known, though the accurate nowcasting remains a substantial challenge [10; 11; 12]. There are many parameters and complex processes at different spatial and temporal scales involved in the generation of severe weather. At the local level, the boundary layer processes, the terrain, and surface effects such as baroclinic vorticity or mountain-valley circulations are present. Furthermore, advective processes such as differential advection, convergence lines and moisture advection must be considered [13; 14]. Finally, there are dynamical processes such as mesoscale instabilities and gravity waves [13]. Besides the study of processes leading to severe weather, another way to improve our understanding of these events is the characterization of the environmental conditions in which these systems form, as well as the observation and quantification of the spatio-temporal distributions of severe weather systems themselves. The detection and monitoring of deep convection and associated severe weather and the characterization of the environments in which they form are based on on different perspectives. The ingredients-based approach [15] with reanalysis data, in which relationships are based on parameters as the convective available potential energy (CAPE) and deep-layer shear for the determination of severe weather environments, is one of the most employed methods. For example, in [PERSON] et al. [16] reanalysis data are used to estimate the frequency of favorable conditions to compute the spatial distribution of severe thunderstorm and tornado environments on a global scale. Furthermore, soundings and ground-based observations are widely used to forecast, detect and monitor deep, moist convection and associated severe weather. For example, in [PERSON] et al. [17], a large set of sounding measurements is combined with ERA-Interim reanalysis to assess the spatial and temporal distributions of the prerequisites of deep, moist convection across Europe.