The National Weather Service has issued a high wind warning for the area and the weather folks are telling Seattle to batten down the hatches:
A powerful area of low pressure is forecast to barrel ashore near the southern tip of Vancouver Island just after midnight on Monday, then track eastward into the mainland of southern British Columbia in the pre-dawn hours. Current weather models have the low deepening to around 975 millibars before landfall—a pressure low enough to generate fairly strong winds across all of Western Washington
In addition, the expected track of the low is close to ideal for a decent Western Washington windstorm, as several of the region’s high wind events have come from lows following a similar path. This includes the devastating Hanukkah Eve Windstorm of December 2006 that also slammed into southern Vancouver Island—although, importantly, the low in that storm was a bit stronger, with a central pressure near 970 millibars before landfall.
Winds should peak around the time people are heading into work Monday morning before subsiding later that morning.