Well, as usual there is a long story behind these and a short story. The short one is that this afternoon returning from Shinagawa, not far from Tokyo Bay and Tokyo Tower for that matter, I looked up and saw these clouds. Meterologists now believe cloud formations of this type - long, contrail like clouds in the evening sky - may be due to electronic perturbances from quartz rock under immense pressure. 5-7 days before a major earthquake.