Objective: To develop and validate a scale measuring health beliefs about UV in cloudy climates that may impact UV exposure behaviors. Participants: Students at a large university in Oregon completed pilot (N = 115) and final (N = 335) scales online March-July, 2016. Five participants underwent cognitive interviews. Methods: Expert feedback, cognitive interviews, and pilot data guided item development and refinement. We conducted factor analysis and invariance testing. Results: The final four-factor model fit well (X[superscript 2] = 37.97, df = 37, RMSEA = 0.000, CFI = 1.000). HBAU subscales are "Sunscreen Toxicity," "Seasonal Effects," "Health Benefits of Tanning," and "Tanning Through the Winter." Invariance testing supported strong invariance across sex and tanning status. Conclusion: The HBAU measures beliefs that encourage UV exposure and discourage protection (eg, the belief that sunscreen ingredients are toxic). This scale will enable more comprehensive measurement of cognitive predictors of UV exposure for student health, clinical, and research purposes.