Cherry Blossom Forecast 2019

When is the Cherry Blossom Forecast 2019 announce?

Some sensational services will publish their first forecasts in early January. Proper services, incl. japan-guide.com, start publishing them around mid to late January or early February. Early forecasts tend to be highly unreliable.

You can look through these forecast sights for starters:
http://www.jnto.go.jp/sakura/eng/index.php
https://s.n-kishou.co.jp/w/sp/sakura/sakura_top.html
https://www.kyuhoshi.com/japan-cherry-blossom-forecast/
http://sakura.weathermap.jp/
http://www.rurubu.com/season/spring/sakura/

I suggest you start around mid-February or so, and check back from time to time. You can only forecast the season about a month or so before it begins, and even then, weather could delay or accelerate by a few days. It would be better to keep a flexible schedule.

Forecast: There will be cherry blossom!

And the season will stretch for months and across Japan!

Strewth - it really doesn't matter the precise day for peak blossom when there is so much variety across the country. Pick a date and consider plus/minus two weeks of average will still deliver good blossom.

For example, this year I toured with guests across four weeks hitting Kyoto several times - in each trip we had great blossom from mid-March to mid-April. Even Shinjuku National Gardens have information boards noting the six weeks they expect cherry blossom in the park.