Trader sentiment for Seattle's highest temperature on May 15 heavily favors 57°F or below at near-certainty, driven by confirmed National Weather Service observations showing persistent marine layer clouds and onshore flow that suppressed daytime warming. These conditions aligned with typical mid-May climatology for the Pacific Northwest, where average highs hover near 65°F but frequently drop under stratus cover, limiting solar radiation and keeping surface temperatures well below seasonal baselines. Recent model runs from the National Centers for Environmental Prediction reinforced this outlook with minimal warming expected through the afternoon. The sole scenarios that could realistically shift resolution involve station-specific measurement errors or rapid cloud clearance not captured in final data, though neither occurred.