<p>Reef degradation induced by climate change is motivating interest in active management strategies to retain living coral cover including coral restoration. Understanding the level and range of heat tolerance available in coral populations is critical to determining their viability and may be important in choosing corals to propagate for restoration projects. There is a need to assess heat tolerance experimentally and to relate experimental performance to real-world bleaching conditions and outcomes. We sampled a model population of a key reef-building coral (<i>Montipora capitata</i>) in Kāneʻohe Bay, Oʻahu, Hawaiʻi and subjected fragments to an artificial heat stress profile. We subsequently revisited and assessed source colonies at the height of a natural bleaching event. Measurements of photosystem efficiency taken on samples during artificial heat stress were predictive of subsequent field bleaching responses of source colonies. By including experimental performance in additive modeling along with previous measures of symbiont community and source site characteristics, we improved predictions of later field outcomes. Survival of coral samples measured several months after experiencing the heat stress had strong positive predictive value for bleaching outcomes but also produced many false negatives. These results support the notion that heat tolerance is a complex trait with detectable partitioning of its underlying sources. This work reinforces the utility of heat-based experimentation both for understanding the biological underpinnings of heat tolerance and for gleaning information about individual corals that has direct applicability for conservation forecasting and restoration activities.</p>