I show a candidate destination list prepared for a visit window of Apr 10-23 here.
https://www.japan-guide.com/forum/quereadisplay.html?0+162429But, be careful. The forecasts are fluctuating. Takato has moved a few days earlier since the above.
Apr 6-12 Nagano/Takato (JR Inashi, 25 min bus, 15 min walk)
https://weathernews.jp/s/sakura/spot/165/index.htmlIn the same framework above, this is a new list for Apr 13-19.
Apr 8-14 Fukushima/Miharu Takizakura (JR Miharu, 20 min bus)
https://weathernews.jp/s/sakura/spot/71/index.htmlApr 9-15 Niigata/Muramatsu Koen (JR Gosen, 15 min taxi)
https://weathernews.jp/s/sakura/spot/226/index.htmlApr 9-17 Nagano/Kaikoen (JR Komoro, 3 min walk)
https://weathernews.jp/s/sakura/spot/162/index.htmlApr 10-13 Nara/Yoshinoyama/Okusenbon (Kintetsu Yoshino)
https://weathernews.jp/s/sakura/spot/6408/index.htmlApr 10-15 Nagano/Garyu Koen (JR Nagano, Nagaden train to Susaka, 20 min walk)
https://weathernews.jp/s/sakura/spot/4803/index.htmlApr 11-16 Fukushima/Tsurugajo (JR Aizu-Wakamatsu, 5 min bus)
https://weathernews.jp/s/sakura/spot/70/index.htmlApr 11-17 Yamagata/Tsuruoka Koen (JR Tsuruoka, 30 min walk)
https://weathernews.jp/s/sakura/spot/57/index.htmlApr 12-15 Osaka/Zoheikyoku (JR Osaka-Tenmangu, 15 min walk)
https://weathernews.jp/s/sakura/spot/318/index.htmlApr 13-17 Niigata/Ogozu Bunsui (JR Bunsui, 20 min walk)
https://weathernews.jp/s/sakura/spot/227/index.htmlApr 14-19 Yamagata/Eboshiyama (JR Akayu, 20 min walk)
https://weathernews.jp/s/sakura/spot/63/index.htmlApr 17-24 Ibaragi/Shizumine Furusato Koen (JR Shizu, 30 min walk)
https://weathernews.jp/s/sakura/spot/4001/index.htmlThe above are only selected from the Sakura 100 in Japan. You could find more secondary Sakura sites but more popular ones. From a list by Japan-Guide, you may pick up Fuji Five Lakes, Takayama, Kitakami, and Hirosaki, now.
https://www.japan-guide.com/sakura/This is a search tool by WeatherNews. You just need to select place and date.
https://translate.google.com/translate?sl=ja&tl=en&js=y&prev=_t&hl=ja&...Or, just click here on the day of a visit. They show a list of the best sites of the day.
https://hanami.walkerplus.com/list/ss0004/