National Weather Service guidance and ensemble model runs for coastal Los Angeles stations project an August 20 high near 78–81°F, driven by a persistent marine layer and moderate onshore flow off the cooler Pacific that caps afternoon heating. This pattern, reinforced by weak upper-level ridging and typical late-summer climatology, keeps the daily maximum well below inland peaks exceeding 90°F. Recent observations confirm the marine layer’s depth and stability, with minimal model disagreement supporting the current trader consensus around 80–81°F as the modal outcome while leaving modest probability for slight warming or cooling depending on the exact timing of any onshore surge.