Predictions for the typhoon are considerably less dire today. The current prediction is that it will be a category 1 (not 4) when it is closest to Kumamoto and, judging from images of the predicted path, it may be far enough north so as not to be a major problem for Kumamoto.
The image is from
https://www.wunderground.com/hurricane/western-pacific/2016/Typhoon-Chaba
The site I have referred to earlier
is offering similar projections.
– Kirk