Lake ecosystems are sensitive to local weather conditions, and especially to extremes such as storms and heatwaves. Here we provide an overview of the shorter and longer term effects on lake physics, chemistry and biology. Use of high frequency data from in situ sensors to monitor lakes has provided new insights into these impacts. Many knowledge gaps still exist, however, particularly in relation to the effects on emissions of greenhouse gases from lakes, short-term changes in lake nutrient dynamics, and effects on lake biological communities, parameters for which high frequency data are still scarce.