It was the business of the meteorologists to determine which was the best day in the month of May for the start. With “Fram’s” experiences before us the prospects of finding a good starting day were not very rosy. In May, 1896, when “Fram” was about halfway between Spitzbergen and the Pole, there were twenty-five days with rainfall, and only three days at the beginning of the month had clear weather. Should May, 1925, turn out just as bad as May, 1896, the polar flight would take place under very risky meteorological conditions. What resources were now at our disposal to determine what kind of weather was expected? First were the telegrams from the stations in the neighborhood, indicating the kind of weather which was approaching. This system is commonly used by all meteorological institutions which have something to do with weather reports, and it was therefore only natural that this should be made use of for the polar flight. One can, however, know beforehand that to make weather forecasts at Spitzbergen is much more difficult than at other places where it has been tried before. For instance, Southern Europe is covered by a network of telegraph stations which can report the approaching weather. But in Spitzbergen it is not so easy. The network of European stations certainly give reports of every condition approaching from the south, but no telegraphic weather reports can be obtained from the west, north, or east. There are, therefore, many situations where the meteorologists, notwithstanding all the aid, can give no reply to the question: “What will the weather be like to-morrow?” And that is the case in Spitzbergen. But the polar flight had to be undertaken from there, and had to extend more than 1,000 kilometers above unknown regions in unknown weather conditions! How could any one guarantee good weather for the whole distance? I know that many meteorologists would reply to such a question that this is beyond science. To prophesy what the weather will be like near the Pole is pure guesswork. As now and again stress has been put upon this view in the press, may I be permitted to defend the foolhardiness I showed by venturing to tackle this problem? I admit that it is very often quite impossible to say what the weather will be like on the way from Spitzbergen to the Pole, and still less possible to predict how it is likely to turn out in a day or two’s time. But meteorology allows us to determine by indirect conclusions whether the prospects of good weather are bright or whether the situation is too risky. That these weather forecasts are based on very weak foundations, and therefore can easily turn out wrong, was known by the airmen from the first hour. Still they preferred to follow the advice science could give, even if it was often vaguely formulated and given with all sorts of provisos.