The impact of meteorological conditions on the occurrence of various cardiovascular events has been reported. The aim of this work was to study the correlations between weather conditions and the occurrence of type A acute aortic dissections (AADs). Between 1997 and 2007, all the medical records of patients who underwent surgery for type A AADs in Toulouse University Hospital (France) were reviewed. The clinical data were confronted with the meteorological data provided by the French national meteorological office (MétéoFrance) over the same period. Two hundred and six patients with spontaneous type A AADs underwent surgery during this period. The incidence of aortic dissection was higher in winter time than in summer (P=0.018). The days with aortic dissections were colder than those without aortic dissections (P=0.017). Statistical analysis highlighted a decrease of atmospheric temperature during the three days preceding the upset of the symptoms (P=0.0009). This work demonstrates a correlation between spontaneous type A AADs and low atmospheric temperature.