- The cool circulation pattern experienced in September continued in October ushering in one of the coldest Octobers in a long time. However, contrary to the wet September experienced in much of the west, October was moderately dry (PNW) to extremely dry (California).
- The cool September and October added little no heat accumulation and was one of the coolest endings to a vintage in roughly 30 years. Overall accumulation ended above the long-term averages for most locations across the west, albeit near the average of the last 15 years or so.
- The forecast through mid-month indicates the continued dominance of high pressure over the region that has brought clear skies, cold nights, foggy mornings, and air stagnation to many in the PNW. Winds in California should remain below the extremes of the last month or so, but drought concerns continue due to prolonged lack of rain and little forecasted through the month of November.
- The first half of winter forecast hints at a near normal to slightly warmer than normal western US while the eastern half of the country will likely be much colder than normal. The precipitation forecast for DJF is indicating near-average conditions in the PNW while tilting the odds for portions of California and Southern Oregon to remain dry during the first half of winter.