Current National Weather Service short-range guidance and ensemble models show Seattle’s daytime high on May 17 centered near 61 °F, with marine-layer stratus and moderate onshore flow limiting afternoon warming. This consensus keeps the 60–61 °F and 62–63 °F bins tightly matched at roughly 31–32 % each. Minor differences among model runs arise from the exact timing of cloud clearance and subtle ridge strength over the Pacific Northwest, which can shift the peak temperature by 1–2 °F. Historical May climatology places Seattle’s average high at 64 °F, but persistent cool marine influence has kept recent daily maxima 2–4 °F below normal, reinforcing trader emphasis on the lower-60s outcomes. Updated model cycles expected within the next 24–36 hours will further narrow the range.