National Weather Service forecast models project a daily high of 58–59°F at Seattle-Tacoma International Airport today, driving the 84.5% market-implied probability for that bin. Persistent onshore flow from the Pacific and a stable high-pressure ridge maintain moderate temperatures without significant warming aloft or downslope effects that could push readings higher. Historical mid-May climatology for the region centers around the upper 50s to low 60s, and current numerical guidance shows tight model consensus with minimal spread. Traders are weighting the absence of late-day clearing or stronger solar heating that might otherwise elevate the peak, leaving only slim odds for adjacent ranges. Resolution depends on the official maximum reported by the end of the calendar day.