Matsushima Bay is a beautiful coastal area near Sendai and a popular tourist destination. We visited there almost 3 years ago. Higashi-Matsushima City (East Matsushima) was hit by a 10 meter tsunami. Higashi-Matsushima is east of the bay and unprotected. The bay is better protected and may have been spared, but have not found any info about it. A picture from on our visit to Matsushima almost 3 years ago.
Update: NHK reported that 300 people had safely evacuated to Zuiganji Temple in Matsushima Bay (瑞巌寺). From other non-official postings, it appears the damage to Matsushima Bay was minimal.
Matsushima, like may other coastal areas had an abundance of tsunami evacuation signs.
From the Fuji News stream of the damage to Higashi-Matsushima. The damage extended several kilometers inland, even taking a train.
Hachinohe was also hit by a 2.5 meter tsunami. We had a good sushi dinner in Hachinohe on the same trip 3 years ago. We passed through Hachinohe and Sendai on our way back from Hokkaido last month.