Forecast models from the National Weather Service and supporting numerical guidance currently project a daily high near 63°F at Seattle-Tacoma International Airport on May 18, placing the outcome well above the 58°F threshold and aligning with the market’s dominant 99.2% implied probability for that bin. This expectation reflects typical mid-May climatology in the Pacific Northwest, where onshore flow often stabilizes daytime temperatures in the low-to-mid 60s, combined with the absence of any strong cold-air advection or marine layer strengthening in the latest runs. Minor uncertainty remains from potential shifts in the 850-hPa thermal ridge or unexpected cloud cover that could trim the high by a degree or two, though such revisions would still keep readings above 58°F in nearly all ensemble members.