Western Washington is subject to various local storms that affect the Pacific Northwest throughout the year, such as wind, snow, ice, hail and potentially tornadoes. Although rare, tornadoes are the most violent weather phenomena known to man. Their funnel shaped clouds rotate at velocities of up to 300 mile per hour and generally affect areas up to a mile wide and seldom more than 16 miles long. Four tornadoes have been sighted in King County since 1950.

The western part of the Puget Sound region was heavily hit by the wind storm that struck on January 20, 1993, Inauguration Day. High winds caused tremendous destruction of public and private structures, power and telephone lines, and trees; South King County was particularly hard hit. Over 280,000 of Puget Power's King County customers were without electricity; damages to Puget Power facilities were estimated around $17 million.

Six other major wind storms have occurred in Western Washington since 1945. The Tacoma Narrows Bridge (1940) and Hood Canal Bridge (1979) were blown down during two of these storms. However, the most severe windstorm to affect this region was the 1962 Columbus Day storm. Sustained winds over 85 mph were recorded; 46 people died and 53,000 homes were damaged throughout the region.

The Puget Sound Region is vulnerable to the various severe local storms except for dust storms which occur east of the Cascades in the dryer areas of the state. Western Washington has had an average of 11.4 inches of snowfall annually over the past 30 years. Snowfall records in the region are: one day record: 21 inches in January 1950; one month record: 57 inches during January 1950; and winter long record: 67 inches during the winter of 1968-1969. This shows that King County is quite vulnerable to the affects of snow and ice each winter; windstorms generally occur between October and April as well. The current utilization of above ground utility lines increases the vulnerability to widespread utility outages during these weather events (See section L for more detailed information on utility outages). Additionally, people in transit are considered the most vulnerable group because mobility is often rapidly reduced trapping people without the necessary resources. Staying home when such events are forecast is typically the wisest course of action.

The general effects of most severe local storms are immobility and loss of utilities. Transportation routes can get blocked, travelers and commuters can get stranded, and families can be separated. Additionally, because electrical lines are damaged, other utilities such as telephone systems (cell and land lines), natural gas, water and sewer systems can become inoperable. Physical damage to homes and facilities can occur from wind damage, accumulation of snow, ice, and hail from accompanying winds. Even a small accumulation of snow can wreak havoc on transportation systems due to a lack of snow clearing equipment and experienced drivers.

Storms like these can quickly overwhelm city and county resources. Citizens should be prepared for these types of storms: family plans should be developed, disaster kits should be put in homes, workplaces, schools and cars and every family member should be taught how to shut off household utilities. Sending children home early from schools and letting employees leave early should be encouraged.