Adam when on to the WENB forums and made a post on there to let PES Fans know what will be missing from PES 2014 and the reasons that they will not feature.
PES 2014 will not feature rain weather effects and will also not feature any Spanish Stadiums this year which is a loss as last year PES 2013 had every La Liga stadium.
The option in edit mode to create your own stadium has also been removed this year.
Adam goes into detail explaining that EA have been "extremely aggressive" with there capturing of licenses with clubs and leagues this year. This is the reason they are not allowed to include Spanish stadiums or a stadium editor and it is not due to any technical issue.
Not having rain included is due to a technical issues and time restrictions with the release getting very close. It was always in there plans to feature Rain as a weather effect and also have it effect the game play on the pitch as rain would in real life.
I would highly recommend reading Adams full post on there matters to fully understand y they will not feature in PES 2014.
Hopefully that is all the bad news out of the way and we can look forward to a great and exciting new game which PES 2014 promises to deliver on the pitch.