Abstract
In the summer of 1952, the weather of Japan was bad, and the number of rainy days was greater than in the normal year. The cause of this weather seems to the author to be that the frontal zone stagnated along the south coasts of Japan and was closely related to the cut-off cold vortex in the upper air over Manchuria. In the lower layer of the cold vortex the pressure was lower than in the surrounding pressure fields, so that the divergence in the lower layer was weak and the dissipation of the cold vortex was also not remarkable. Moreover, it was found as a result of aerological analysis that the strong westerly (Jet Stream) was stagnant over the stationary front and that the inverse meridional circulation was situated around the Jet.
