Thunderstorms in the Southern Great Plains of the United States are among the strongest on Earth and have been shown to be increasing in intensity and frequency during recent years. Assessing changes in storm characteristics under different climate scenarios, however, remains highly uncertain due to limitations in climate model physics. We analyse oxygen isotopes from Texas stalactites from 30–50 thousand years ago to assess past changes in thunderstorm size and duration using a modern radar-based calibration for the region. Storm regimes shift from weakly to strongly organized on millennial timescales and are coincident with well-known abrupt climate shifts during the last glacial period. Modern-day synoptic analysis suggests that thunderstorm organization in the Southern Great Plains is strongly coupled to changes in large-scale wind and moisture patterns. These changes in the large-scale circulation may be used to assess future predictions and palaeo-simulations of mid-latitude thunderstorm climatologies.

美国南部大平原的雷暴是地球上最强的雷暴之一，近年来其强度和频率都在增加。然而，由于气候模型物理学的局限性，评估不同气候情景下风暴特征的变化仍然高度不确定。我们分析了 30-5 万年前得克萨斯州钟乳石的氧同位素，以使用该地区基于现代雷达的校准来评估过去雷暴大小和持续时间的变化。风暴状态在千年时间尺度上从弱组织转变为强组织，并且与上一个冰河时期众所周知的突然气候变化相吻合。现代天气分析表明，大平原南部的雷暴组织与大规模风和水分模式的变化密切相关。大尺度环流的这些变化可用于评估中纬度雷暴气候学的未来预测和古模拟。