ANALYZING HISTORICAL TEMPERATURE AND PRECIPITATION TRENDS FOR THE LOWER RIO GRANDE VALLEY, TX

Changing climate baselines and intensifying extreme weather events impact human and environmental systems globally, with some climate models forecasting that these extremes will continue to intensify. Understanding how climate change is affecting the Lower Rio Grande Valley is of particular interest given that the region sits at the interface of subtropical, coastal, temperate, and desert climate types. In this study, a 70 year long (1950-2020) time series of temperature and precipitation for the three cities of Brownsville, McAllen, and Rio Grande City was scrutinized to identify climate trends within the unique and highly variable climate of the Lower Rio Grande Valley. Analysis includes identifying changes in annual precipitation and temperature data, as well as identifying changes in extreme temperature and precipitation events. Linear regression analysis of temperature trends over the past 50 years show a positive increase in average annual temperatures. Analysis of monthly data suggests that there has been a statistically significant increase in temperature for the months of May – September between two periods of 1960-1970 and 2010-2020. These changes in regional temperatures demonstrate that the Lower Rio Grande Valley region is experiencing changes in climate trends, which might extend to precipitation and affect the region’s environment. Determining how the climate and extreme events are changing in the Rio Grande Valley is important for local stakeholders, such as city officials and farmers, in preparing for these extreme events