The main cherry blossom season (Sakura) has ended or is drawing to an end in many cities across southern and central Japan, including Tokyo and Kyoto. Meanwhile, the blossom front is moving into northern Japan and higher elevations. (Excellent viewing to come in Canada and Northern United States) Rain, wind and temperatures can have a strong effect on the process of the season, for example, they can delay or shorten it considerably.
From the Japan-Guide (this is a hoot).....Therefore, use the forecasts at your own risk.
Hanami literally means "flower viewing", however, it commonly refers only to cherry blossom viewing. Cherry blossom viewing is easy: Simply enjoy the intensity of the many blossoms by looking at a single tree or a group of trees. From a distance, the trees appear as beautiful clouds, while the beauty of single blossoms can be enjoyed from a close distance. Cherry blossoms are also especially beautiful in combination with a castle, temple or shrine. In some places the blossoms are lit up in the evening, which makes an amazing sight.
I really love this description of The Colour of Spring in Japan:
Among the spring flowers, cherry blossom is the most iconic in Japan. For people here, the cherry blossom romantically describes the ephemeral nature of life. The flowers have sensitive pale pink colors that shine gracefully both by day and when illuminated at night. They bloom at only the perfect temperature and last only a week – if the weather isn’t stormy. The flowers are so fragile that even a warm spring rain can easily cause the blossoms to fall. In addition to the general floral beauty of the cherry blossoms, the way the flowers fall is sentimental. People usually say that cherry blossoms don’t fall but scatter, because each petal falls from its branch like a snowflake. The cycle of the cherry blossom reflects the Japanese idealism of the ancient samurai spirit, which believed that life was brief and beautiful just like the cherry blossoms. - Japan National Tourist Organization.