I saw a segment about this on RKK’s local news.
You can see some pictures that look a bit more like what I saw on local TV (submissions from ordinary viewers) here
https://weathernews.jp/s/topics/201801/180055/
and here
https://twitter.com/souki_e/status/953747110251278336/photo/1
As the article explains, these clouds were caused by today’s early-morning launch of the Epsilon-3 rocket.
– Kirk
