National Weather Service guidance and ensemble models currently project a Seattle high near 62 °F for May 17, driven by persistent onshore flow from the cool Pacific that moderates daytime warming in the city’s maritime climate. This forecast places the most probable outcome in the 62–63 °F or 64 °F-and-higher ranges, aligning with trader-implied probabilities of 35 % and 45 %, respectively. Mid-May climatology for the region typically clusters highs in the upper 50s to low 60s, and the absence of strong warm-air advection or clear-sky heating supports this narrow distribution. Updated model runs through the morning continue to show limited variability, though any late-day shift in marine layer depth could nudge readings into the upper 60s before official Sea-Tac Airport observations finalize the market.