Recent National Weather Service guidance and ensemble model runs indicate a high near 79–82°F for Seattle on August 21 under weak upper-level ridging and persistent low-level onshore flow from the Pacific. This marine influence, combined with partly sunny skies and light northwest winds, caps daytime heating near climatological norms for late August while limiting marine-layer stratus development. Trader consensus centers on the 80–81°F and 82–83°F bins because small differences in afternoon cloud cover, sea-breeze timing, or slight ridge strength can shift the peak by 1–2°F. No major frontal systems or thermal troughing are expected before resolution, keeping the distribution tightly clustered around these values.