In Your Lifetime
There is a HIGH CHANCE (84%) of a magnitude 6.5+ deep earthquake hitting in the next 50 years. It will feel similar to the M6.8 Nisqually Earthquake in 2001. Strong shaking will make it hard to walk here. Books, glassware, and items will fall from shelves. Cabinet doors and drawers will open. Some chimneys and poorly built buildings will be damaged.(map)
There is a MODERATE CHANCE (10-30%) of a magnitude 8+ Cascadia earthquake hitting the Northwest in the next 50 years. When it does, you will feel very strong shaking that persists for minutes here. Standing will be difficult and many will be injured. Bricks and shattered glass will litter the streets. Power and water will be off for days to weeks. (map)
What's the Worst?
A LOW CHANCE (5%) exists of a magnitude 7+ earthquake on the Seattle Fault in the next 50 years, but if it does it will be damaging. Severe shaking will make it hard to stand or drive. Heavy furniture will be overturned. Parts of URM buildings will collapse and wood frame houses will shift on foundations.(map)
Shaking soils will become very unstable and will behave like quicksand. Sand-filled water may come up through cracks in streets. (map)
VERY HIGH DENSITY: 100 to 250 unreinforced masonry (URM) buildings per square mile.
If you are in a URM during an earthquake Drop, Cover, and Hold On. In these buildings strong earthquake shaking will cause brick walls and roofs to fail. Debris will litter the streets. See where the URMs are nearest you and if they've been retrofitted. (map)
Scientists cannot predict when an earthquake will happen so be aware and if you feel shaking, drop cover, and hold on. An early warning system is currently being developed for the West Coast. You can find out more here.