The word for
at the start of Jeremiah 9:19 means that what follows is an explanation for the need to call the mourning women. Wailing has already begun in Zion. Only once the invasion has actually started and Jerusalem is being overrun by the invading force will the people realize that Jeremiah was right and that the time for mourning has come.1
The mourning no longer consists of wailing only, but words are spoken by the people. They are ruined and utterly shamed. The invading forces will bring utter destruction and Judah will lose her standing as a nation. This shame has come because they have been forced to leave the land and their homes have been destroyed.
19 Car des cris lamentables se font entendre de Sion: Eh quoi! nous sommes détruits! Nous sommes couverts de honte! Il nous faut abandonner le pays! On a renversé nos demeures!