National Weather Service forecasts project Seattle highs in the mid-to-upper 80s on August 5 under sunny conditions, light northeast flow, and patchy smoke from regional wildfires, with marine air moderating peaks near the coast. This aligns with the market's emphasis on 86-87°F as the leading outcome at 38.5% implied probability, ahead of 84-85°F, as short-term model runs show limited additional warming from the offshore ridge before a thermal trough weakens later in the week. Above-normal summer guidance from NOAA supports the upside skew relative to the early-August climatological average near 79°F, though ensemble spread keeps lower bins viable if onshore flow strengthens sooner than expected.