2009 Hazard Mitigation Plan
Severe weather can affect all areas of Shoreline. Strong wind mainly comes from the west and southwest. The wind flows from high to low sea-level pressure through the Chehalis Gap to the south and the Strait of Juan De Fuca to the north. The convergence of these two wind flows is known as the Puget Sound Convergence Zone. The convergence usually forms in an east-west line across southern Snohomish County but can go as far north as Anacortes or as far south as Federal Way, depending on where the winds collide shows the air flow of the Puget Sound Convergence Zone. Ice will more likely affect those areas at a higher elevation, such as the Highlands or parts of Innis Arden.
Since the entire city is susceptible to severe weather, all critical infrastructure is considered exposed to severe weather. Given that electrical utilities and roads are most often affected by severe weather, all critical infrastructure managers and operators should plan for possible power outages and difficult ingress and egress. Some critical infrastructure, such as power lines, is actually more likely to be impacted or damaged as a result of severe weather.