Can we predict the extreme? Assessing the skill of seasonal forecasts in capturing the 2024 European heatwave

Abstract Eastern Europe experienced a pronounced warming trend in the summer of 2024, with average maximum temperature anomalies reaching 3.35 ∘ C in June and 3.73 ∘ C in July, and minimum temperature anomalies averaging 2.17 ∘ C in June and 2.60 ∘ C in July, significantly exceeding the 1991–2020 climatological baseline. Moreover, three distinct heatwave events were identified: 3–11 June (9 days), 17 June–1 July (15 days), and 6–21 July (16 days), highlighting the prolonged and intense nature of the heat stress. Seasonal forecasting systems (GCFS, SEAS5, and Météo-France) consistently demonstrated the capability to predict above-climatological-mean temperatures over the Eastern Mediterranean, particularly the Balkan Peninsula, showcasing robust regional warming trend capture, though with variations in accuracy across lead times. The accurate prediction of subtropical influences, as evidenced by consistent positive temperature anomaly forecasts over North Africa and the Iberian Peninsula, underscores the forecasting systems’ capacity to represent large-scale circulation patterns, yet the predictive skill for midlatitude blocking events and their spatial extent remains subject to limitations and model-specific variations. Despite the inherent limitations in long-range meteorological predictability, particularly concerning heatwave timing and location, the study emphasizes the critical imperative for continued refinement of seasonal forecasting models to enhance societal resilience against the escalating impacts of climate change, particularly through improved representation of synoptic atmospheric drivers.