A big typhoon (Lionrock in English, #10 in Japanese) is approaching the northeast part of Japan as of Aug 30, 2016.
Twenty two lines of Tohoku Shinkansen and Hokkaido Shinkansen are suspended due to this typhoon.
Latest status / suspension info of Tohoku Shinkansen can be checked on the website below which JR-EAST provides.
Latest status / suspension info of Hokkaido Shinkansen is not available in English on the internet. JR Hokkaido provides this info only in Japanese as below.
Please check the latest information at the local station, hotel, etc.
Your seat is reserved and secured when you book your tickets. Head to the station with a peace of mind.
Better seats and free blankets. Popular among Japanese business persons, executives and people who
Know as "First Class" of Shinkansen seats. Only available on Hokuriku and Tohoku Shinkansen lines.
You can take any open seats in unreserved cars of any train on the departure date. (No departure time will be indicated on your tickets.)
The best seat type if your priority is the cost and are traveling during less-crowded season/time.
For further information and photos, please visit official page at http://www.jreast.co.jp/e/ticket/types.html