Little is known about the climate of southern Australia during the Last Glacial Maximum and deglaciation owing to sparse records for this region. We present the first high-resolution data, derived from speleothems that grew 23–5 ka. It appears that recharge to the Flinders Ranges was higher than today, particularly during 18.9–15.8 ka, argued to be due to the enhanced availability of tropical moisture. An abrupt shift to aridity is recorded at 15.8 ka, associated with restored westerly airflow.