Abstract
Author has been engaged in research on above-captioned subject continually with field work data and found the following facts through the analytical study. The conflagrations, in which burnt down more than 500 houses, were much influenced by an extraordinary dry strong wind, blowing at the time of break out of fire.
The nature of these winds can be classified into the following four points :
1) Strong winds connected with conflagrations were almost dry and over the with scale 3 (velocity over 5m/sec) and blowing about over 5～20 hours.
2) The conflagrations occurred in “San-in & Hokuriku” regions which broke out from April to October were very much influenced by cyclones from the Asian continent and the Typhoons passing through the “Kyushu” region from south to north and those Typhoons moving to NNE direction in Japan Sea.
They have some tendency to cause the Foehn and found that these phenomena have great relation to the occurrence of conflagration in “San-in & Hokuriku” regions.
3) Conflagrations in winter season (from Nov. to Mar.) have been greatly influenced by the winter monsoon blowing from Siberian region. Distribution of atmospheric pressure, on that occasions, were almost high in the south and low in the north.
4) At the time the fire broke out, there was no relation on the time of beginning of blowing of strong wind but was found that almost same time when the wind velocity reached the peak and humidity relatively low. And also it was almost at the same time that the time of extinguishment of the fire and wind direction change and wind velocity became weak.
