The closely matched probabilities across Seattle’s July precipitation bins reflect substantial uncertainty in Pacific Northwest summer rainfall totals, historically averaging just 0.6–0.7 inches under the dominant influence of the North Pacific High, which typically suppresses storm tracks. Emerging El Niño conditions and seasonal outlooks favoring warmer, drier western Washington add downward pressure on totals, yet occasional convective showers or weak frontal passages can still push accumulations higher. With only the first ten days observed, traders weigh model consensus on ridge strength and jet-stream positioning against historical variability that produces sub-0.5-inch or 1–2-inch outcomes in roughly equal measure, pending updated NOAA forecasts.