Background: Hurricane Harvey struck southeast Texas in August 2017 resulting in widespread destruction and significant emotional distress. Objective: We examined the effectiveness of a transdiagnostic psychotherapeutic intervention delivered to youth with emotional disorders in a large, community health system following this hurricane. Methods: One hundred forty-nine youth aged 5 to 17 years with a history of hurricane exposure and emotional difficulties received an average of 6.4 (SD = 3.4) psychotherapy sessions using the Unified Protocols for Transdiagnostic Treatment of Emotional Disorders in Children and Adolescents. Youth-caregiver dyads completed measures of disaster exposure and impact at baseline as well as anxiety and depression at baseline and each therapy session. Symptom severity and level of functioning were rated by the clinician. Latent growth curve modeling was used to examine symptom change over time. Results: Children and adolescents began treatment with moderate levels of anxiety and depressive symptoms, symptom severity, and difficulties in daily functioning. Anxiety and depressive symptoms and symptom severity declined significantly over the treatment period. Clinician ratings of functionality evidenced significant improvement over time. Older age was correlated with more depressive symptoms at baseline and superior functioning at baseline with fewer completed treatment sessions. Conclusion: In this naturalistic, community-based effectiveness study we found significant improvement on measures of anxiety, depression, symptom severity, and daily functioning. Findings suggest that a transdiagnostic intervention may be effective for addressing a range of emotional concerns in the aftermath of a natural disaster. These results can be used to inform and refine evidence-based interventions that improve the mental health and wellbeing of disaster-exposed youth.