Microrefugia can play an important role in determining biological responses to climate change, but the location and characteristics of these habitats are often poorly understood. Groundwater-dependent ecosystems (GDEs) represent critical climatic microrefugia for species dependent on cool, moist habitats. However, knowledge of the distribution and stability of GDE microrefugia is currently lacking. This challenge is typified within moist portions of the Pacific Northwest, where poorly studied cliff-face seeps harbor exceptional biodiversity despite their diminutive size (e.g., ~1-10m width). To enable future management of these habitats as climatic microrefugia, we modeled the distribution and thermal and hydrologic stability of these seeps across the region. We conducted surveys for cliff-face seeps across ~1,600km of roads, trails, and watercourses in Washington and Idaho and monitored water availability and air and water temperatures at a subset of these seeps. We detected 457 total seeps through an iterative process involving surveying, modeling, ground-truthing, and then remodeling the spatial distribution of seeps using boosted regression trees. Additionally, we used linear and generalized linear models to assess environmental correlates of seep thermal and hydrologic stability. Seeps were generally most concentrated in steep and relatively low-lying areas (e.g., towards the bottom of deep canyons or the base of tall cliffs), and were also positively associated with basalt, glacial drift, or graywacke bedrock, high average slope within 300m, and low average vapor pressure deficit. North-facing slopes were the best predictor of stable air and water temperatures and perennial seep discharge, and relatively low-lying areas also predicted stable seep water temperatures. These findings represent an important first step towards identifying and managing stable seep microrefugia in the Pacific Northwest, and towards safeguarding numerous seep-associated species under climate change. In addition, the iterative method we developed represents an innovative approach that can be used to identify other types of inconspicuous microrefugia.