Deplore, lament, bewail, bemoan mean to manifest grief or sorrow for something. All carry an implication of weeping or crying which is commonly purely figurative.
Deplore implies keen and profound regret especially for what is regarded as irreparable, calamitous, or destructive of something good or worth keeping.
Lament commonly implies a strong or demonstrative expression of sorrow or mourning. In contrast to deplore, it usually does imply utterance, sometimes passionate, sometimes fulsome.
Bewail and bemoan imply poignant sorrow finding an outlet in words or cries, bewail commonly suggesting the louder, bemoan, the more lugubrious expression of grief or, often, of a mere grievance or a complaint.