Puget Sound Convergence Zone Puget Sound Convergence Zone The Puget Sound Convergence Zone (PSCZ) is a meteorological phenomenon that occurs over Puget Sound in the U.S. state of Washington. It is formed when the large-scale air flow splits around the Olympic Mountains and then converges over Puget Sound. This convergence zone generally occurs between north Seattle and Everett and can cause updrafts and convection, which leads to a narrow band of precipitation. A second, weaker convergence zone can occur between approximately Victoria, British Columbia, and Bellingham, Washington, over the San Juan Islands, as a result of southwesterly air blowing from the Strait of Juan
Puget Sound faults lie west of the crustal blocks that underlie the Puget Lowland, and again their possible impact on the Puget Sound region is unknown. One of these faults, the "Sequim Fault Zone" (striking east from the town of Sequim), crosses Discovery Bay (and various possible extensions of the Hood Canal Fault) and bounds the Port Ludlow Uplift ("uplift of unknown origin" on the map); it appears to extend to the Southern Whidbey Island Fault. An "Everett Fault", running east-northeast along the bluffs between Mukilteo and Everett – that is, east of the SWIF and at the southern edge of the Everett