El Niño and La Niña (EN/LN) are quasi-periodic ocean warming and cooling events, respectively, that originate in the equatorial Pacific Ocean. Along with associated changes in atmospheric pressure and wind patterns, these phenomena influence the general circulation of the atmosphere and affect short-term regional climate. Meteorologists characterize EN/LN events through various physical indices that are used for correlations with observed climate conditions such as temperature and precipitation. JMP is ideally suited for visualization and analyses of these data. First, indices for EN/LN events are available for each month since 1950. Monthly averaged data from US weather stations are also available for the same 60-year period. Thus, there is a large data sample available for statistical analyses. Second, several JMP platforms – including distribution, time series, and bubble plots – can be used to process and visualize the data. In this paper, we propose to investigate the EN/LN phenomena interactively using JMP. We shall use historical EN/LN indices, temperature and precipitation data from selected US cities, and climatic normals (means) from the National Oceanic and Atmospheric Administration. The temporal behavior of EN/LN events and their effect on local climate will be presented. Comparisons will be made between the results determined from JMP and known climatic impacts of these phenomena. Increased familiarity with JMP processes and an understanding of the EN/LN phenomena are anticipated takeaways for JMP users.