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The Columbus Day Storm October 12, 1962 PowerPoint Presentation
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The Columbus Day Storm October 12, 1962

The Columbus Day Storm October 12, 1962

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The Columbus Day Storm October 12, 1962

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  1. The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

  2. “Normal” Pacific Northwest Windstorms • Approach coast from a WSW, W, or NW direction. • Strongest pressure gradient ahead of storm. • Wind generally southerly ahead of front. • Once front passes, winds decrease and shift to southwesterly, westerly or northwesterly. • Can occur 13 months out of the year. • Can be very destructive. 100+ winds.

  3. A Typical Normal Pacific Northwest Wind Storm

  4. Columbus Day-Type Windstorms • Travel rapidly across Pacific 40oN or lower • Deep upper level trough 135-140oW • Move north along coast inside 130oW • Light SE winds ahead except where gaps in Coast Range • Strongest winds southerly AFTER low moves north • Favor time of year: October, November and early December • Often contain moisture from tropical storm • Often preceded 24 hours earlier by a weaker storm

  5. Paths of Columbus Day-Type Storms

  6. With the low center off Northern California T = 0

  7. When Low Center is Off NW Washington T + 12

  8. Previous windstorms 1. January 9, 1880: Oregon’s lowest Pressure (963mb, 28.45”) at Astoria 2. October 2, 1967: 115mph Newport; 90mph Morrison Bridge 3. November 13, 1981:100+ mph coast 4. January 21, 1921: 110 kts North Head Light House 5. Lewis & Clark November 22, 1805. Columbus Day-type storm?

  9. Observations from the Corps of Discovery: • Lewis: “rained all day; wind violent from the SE” • Clark: “the wind violent from the SSE.” • Gass: “the wind blew very hard from the south.” • Whitehouse: “A hard Storm arose in the course of last night…the wind high from the S.W.l • Who’s correct? • Perhaps they all are observations were listed as November 22. Who’s correct?

  10. Wind Directions Before and After T = 0 T + 12

  11. What About the Future? • 1. No doubt there will be more • 2. What effect will a warmer ocean have? • 3. Will there be adequate warning? • 4. Will we be prepared? • 5. What effect will demographics have? • 6. That’s it! You’ve been blown away!

  12. GO BEAVS!