Forecast models from the National Weather Service and private outlets show Seattle's August 15 high centering on the mid- to upper-70s, with Sea-Tac airport observations likely resolving the market. Persistent marine air, light onshore flow, and variable afternoon cloud cover are limiting daytime heating and keeping temperatures near seasonal normals around 76–79°F. Minor differences in predicted insolation, boundary-layer mixing, and exact wind direction explain the tight clustering between 73°F or below, 74–75°F, and 76–77°F bins. Warmer-than-average summer conditions have raised baselines slightly, yet no strong offshore flow or clear-sky setup has emerged to push readings into the low 80s. Updated model runs and morning observations will refine the final distribution before resolution.