Based on the observation of 929 patients who had to be subjected to tonsillectomy within a period of twelve months, the authors concluded that the vast majority of post operative haemorrhages occurred during the beginning of a good weather period (clearing from the west), not quite so often during a "Föhn"-period (warm winds from the south). This contrasts somewhat with the observations of other authors who found a connection between haemorrhages and the beginning of a period of bad weather (close and stuffy, increasing humidity, high clouds). The dependence of postoperative haemorrhages on meteorological influences would perhaps give a reason for the hitherto medically unexplainable 40 per cent bleedings. Based on these observations it would be desirable for the meteorologic stations (or the media) to inform the doctors and hospitals about the weather phases.