For weather forecasting in Japan where warm and cold currents are complicated in the neighbouring seas, wide attention must be always payed to their balance. For this purpose water temperatures are informed every day from ships at sea to the Central Meteorological Observatory, and are put on weather charts as well as ordinary meteorological data.
In the present paper it is pointed out that daily pressure distributions in the neighbourhood of Japan are controlled to some extent by the predominance of the Kurile and other cold currents. For example, as for the difference of mean pressures over the Yellow Sea and over North China, the amount of its increase or decrease after six or twelve hours can be well estimated from the area of the cold current occupying the Sea.
