The climatic perturbation at ca. 8.2 kyr B.P. is the strongest short-term climate anomaly within the Holocene. It is generally attributed to a meltwater-induced slowdown of the thermohaline circulation in the North Atlantic. Model simulations and available proxy data suggest that it was strongest in the high to middle latitudes around the North Atlantic. Based on new pollen data from Tenaghi Philippon, northeastern Greece, we provide evidence for a massive climate-induced turnover in terrestrial ecosystems of the Aegean region associated with the 8.2 kyr B.P. event. The reconstructed winter temperature decline of >4 °C is much stronger than suggested by model simulations and proxy data from more northern latitudes of Europe, although the latter provide a direct downstream response to a North Atlantic thermohaline circulation slowdown. We attribute this discrepancy to mesoclimatic effects; a stronger influence of the Siberian High during the 8.2 kyr B.P. event may have enhanced the katabatic air flow from the mountains bordering the study site via a larger, longer persisting snow cover. Our data demonstrate that high-amplitude temperature anomalies and increased seasonality connected to the 8.2 kyr B.P. event may also have occurred in the lower mid-latitudes, much farther south than previously thought. The magnitudes of these anomalies appear to have been strong enough to have seriously affected Neolithic settlers in the northeastern Mediterranean region.