The Wildfire Impacts of the 2017-2018 Precipitation Whiplash Event Across the Southern Great Plains

During March and April 2018, dozens of wildfires burned a total of 556,347 acres across the panhandles of Oklahoma and Texas, resulting in at least two fatalities, dozens of homes destroyed, and over 500 personnel dispatched to fight and mitigate the fires. Before this mega-fire event in the Spring of 2018, this region experienced a highly impactful precipitation whiplash event that occurred during the Fall of 2017. Precipitation anomalies that were 137% of normal during the 2017 growing season rapidly cascaded into drought conditions with precipitation anomalies 21% of normal throughout the cool winter season. Excessive precipitation supported vigorous vegetation recovery and growth, with vegetation indices peaking at approximately 1 standard deviation above average during August 2017. However, the subsequent drought period rapidly desiccated the terrestrial surface. This study aimed to examine the role of preceding precipitation whiplash events in providing fuel for wildfires, with 2017-2018 investigated as a case study. Lag correlation analysis of historical data at our study site showed anomalously high precipitation 8 months prior to Spring wildfires, resulting in a significantly higher number of wildfires and acres burned. This study specifically demonstrates the relationship between precipitation, vegetation, and wildfires for the first time across the Southern Great Plains. Transitions from pluvial to drought conditions and their relationship to wildfires have been studied in depth across regions such as California; however, limited studies have examined their impacts across the Southern Great Plains. Overall, this study highlights the significant role of preceding Fall precipitation whiplash events in fueling Spring wildfires across the Southern Great Plains, particularly exemplified by the impactful 2017-2018 case, highlighting the complex dynamics between extreme precipitation, vegetation growth, and subsequent fire risks in the region.