Synoptic drivers of spring hailstorms in Xalapa, Mexico

In reference to the historic hailstorm that occurred in Xalapa, Veracruz (Mexico) in April 2014, a study was conducted to investigate the causes of this phenomenon. The present study examined the synoptic conditions in the spring season that contributed to 20 hail events in Xalapa from 2012 to 2025. A characteristic spatial configuration of thermal wind was obtained, and a theoretical analysis of the results was performed. We identified eight predominant modes of vertically integrated water vapor flux (VIWVF). A proposal for a hailstorm predictor is hereby submitted. This predictor is founded upon the utilization of VIWVF results, along with a teleconnection between the southern United States (Texas) and the central mountainous region of Veracruz (Xalapa). This teleconnection was identified through a spatial and statistical analysis of the Convective Available Potential Energy (CAPE). This predictor facilitates the generation of a one-day minimum forecast for the Xalapa region. Finally, the relationship between the El Niño-Southern Oscillation and hailstorm activity was examined.