Analysis of Louisiana crisis hotline data reveals that overnight temperatures exceeding 80°F trigger a 30% increase in suicide prevention calls, with the strongest effects occurring between midnight and 6 AM when cooling typically provides psychological relief. The research tracked 15,000 crisis interventions across three years, identifying nighttime heat as a distinct mental health stressor separate from daytime temperature extremes. This finding challenges conventional wisdom that daytime heat exposure drives most temperature-related psychological distress. The mechanism likely involves sleep disruption and circadian rhythm interference, as inadequate nocturnal cooling prevents the restorative processes essential for emotional regulation. Previous heat-suicide research focused primarily on daytime temperatures and completed suicides rather than help-seeking behavior, missing this critical intervention window. The Louisiana data suggests that nights failing to drop below 80°F create cumulative stress that overwhelms coping mechanisms by dawn. This represents actionable intelligence for crisis intervention services, suggesting resource allocation should account for temperature forecasts, not just traditional risk factors. However, the study's geographic limitation to Louisiana's subtropical climate raises questions about generalizability to other regions with different nighttime cooling patterns and baseline mental health infrastructure availability.