Relation between the Path of Pilot Balloon and the weather at Maebashi

[摘要] We have picked up the 1053 data of pilot balloon observation which reached above the height of 2000 meters at the Maebashi Weather Station from July 1932 to April 1942, and carefully divided the types of their paths into 21 classes. We have, also, chiefly examined the form of the winding of paths, statistical characteristics of wind direction and velocity above or below the discontinuous surfaces, and further arranged the corresponding weather frequency tables for to-day, tomorrow and day-after-tomorrow in three classes-fair, cloudy, rainy-after four seasons in the year.Considering the local, topograph, or daily change effects for the paths, we have obtained the following characteristics:-a) clockwise paths of balloons largely occur in the region of rising barometric pressure behind cyclonic area and the attending weather becomes better step by step, but the sharp curve on a discontinious surface may result in bad weather on tomorrow and day-after-tomorrow.b) anticlockwise paths generally result in bad weather excepting the case of summer, when, sometimes easterly winds prevail up to higher levels.c) when the southly components of wind in 2-4km layers are increasing, bad weather is expected.d) it is interesting to remark that the same weather map does not always correspond to the same path.

[学科分类] 大气科学