A Comparison of the Summer 2011 Heat Wave and Drought on the Southern High Plains to previous Extreme Years

The summer of 2011 (June – August) was the warmest on record for much of the southern High Plains, including all of Oklahoma and Texas. Additionally, 2011 was the driest year on record for the South Plains in West Texas. The exceptional dryness led to the most extreme wildfire season on record for the state of Texas with the majority of wildfire activity occurring in West Texas. Total monetary losses due to drought were estimated at $2.4 billion for the South and Rolling Plains of West Texas and $8 billion for the entire state. Composite anomalies for the summer of 2011 were calculated for various atmospheric parameters, including 500 hPa height, 850 hPa temperature, 750 hPa temperature, outgoing longwave radiation, surface relative humidity and soil moisture. These parameters were compared to the 85th percentile of wettest and warmest years and the 15th percentile of driest and coolest years. This was done to determine if there were any similarities or differences that stand out between 2011 and the most extreme years. The composites for 2011 were all similar to those of the most extreme warmest and driest years, and the exceptionally dry weather of 2011 contributed to the remarkably large temperature anomalies observed through the summer. In contrast, the coolest and wettest years tended to exhibit more significant differences than similarities in these parameters when compared with either 2011 or the warmest and driest years.