Persistent high-pressure ridging and a warmer, drier seasonal outlook from NOAA and long-range models have tilted trader consensus toward below-normal September totals in Seattle, where the 1991–2020 average is 1.74 inches. Recent summers of exceptional drought have extended into early fall, suppressing the typical late-month increase in Pacific storm frequency. ENSO-neutral to weak El Niño conditions and a positive PDO phase tend to steer the jet stream northward, reducing orographic lift and frontal precipitation across the Pacific Northwest. Historical September extremes range from near-zero to over 6 inches, but current model runs show limited early-month rainfall and only modest increases later, keeping probabilities concentrated in the sub-2-inch bins while acknowledging forecast uncertainty as the first week unfolds.