Reliability of 1st Sakura dates prediction

Japan Meteorological Association has issued the 1st Sakura date predictions yesterday. Can one assume with a fair degree of certainty that these dates shall remain the same going forward. If no, by when does one get a more accurate and definitive prediction?

Can one assume with a fair degree of certainty that these dates shall remain the same going forward.

No. Humans cannot yet accurately enough predict the temperatures over a 2-3 month period. The predictions are based on rough long-term forecasts that are not accurate enough.

If no, by when does one get a more accurate and definitive prediction?

The predictions become increasingly accurate, but accurate predictions of temperatures usually seem to become possible only for about 10 days in advance. And even then, there can sometimes be big surprises. I remember one year - I think it was 2014 - when even the mid March forecasts were off by an entire week because of an unexpected heat wave. But usually the forecasts tend to be quite accurate by early March. Definitive predictions don't exist for cherry blossoms.

thanks Uji-San...I agree that Man has not yet been able to totally control nature (and hope they never can!) and hence weather related predictions are dicey.However, keeping aside those freaky abnormal warm/cool in between periods of some years, would one assume that these dates can be made a base to plan a travel itinerary and make hotel bookings. I plan to be in the Central and Southern parts of Japan - Kanazawa/Nagano northern limit to Ibusuki as southern limit between 24th March and 14th April.

If I take the 1st prediction of JMC, can I safely assume to catch the peak blooms in say more than half the places in my itinerary.

regards

While I would not count on any January predictions, they tend to be better than just relying on the average dates. In that way, they are useful if you have to make your travel arrangements early.

One weather service frankly publishes the accuracy of its forecasts since 2010. It is highly interesting:
http://sakura.weathermap.jp/result2016.php

Average days off of the January forecast (exluding Northern Japan):
2016: off by 4 days
2015: off by 1.5 days
2014: off by 1.2 days
2013: off by 7.5 days
2012: off by 3.5 days
2011: off by 3 days
2010: off by 5 days

The Japan Meteorological Association stopped making forecasts in 2009. The area is left to private companies these days.

Ignoring the "forecast", cherry blossom faces other issues with the weather even when it does bloom. But, looks like a pretty normal season so far.