Understanding suicide ideation (SI) in adolescents, especially during the high risk time following hospitalization for a suicidal event, is a crucial component of improving risk assessment. Most studies rely on single assessments of SI, despite the potential for SI to vary considerably over time. The present study examined how indices of SI intensity (mean values) and lability (mean squared successive difference values) over a six-month period predict suicide attempts and self-harm, as well as how they relate to psychosocial risk factors and affective functioning, in a sample of 103 adolescents hospitalized for a suicide attempt or significant suicide ideation. Across the sample, SI intensity, but not lability, was associated with suicide attempts and nonsuicidal self-injury at six-month follow-up. SI intensity performed similarly to single time point SI assessments, and its relations were not moderated by SI lability. SI intensity was also associated with borderline personality disorder criteria and a history of sexual abuse. In contrast, SI lability was associated with greater negative affect intensity and lability. These findings suggest that intensity of SI may confer more risk post-hospitalization, and provide support for using these statistical methods to capture two distinct parameters of suicide ideation.