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

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

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A Typical Normal Pacific Northwest Wind Storm

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

The Columbus Day Storm October 12, 1962

Has It Happened Before?Could It Happen Again?

George R. Miller

Page 2: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

“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.

Page 3: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

A Typical Normal Pacific Northwest Wind Storm

Page 4: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

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

Page 5: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

Paths of Columbus Day-Type Storms

Page 6: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

With the low center off Northern California

T = 0

Page 7: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

When Low Center is Off NW Washington

T + 12

Page 8: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

Previous windstorms1. January 9, 1880: Oregon’s lowest Pressure (963mb, 28.45”) at Astoria2. October 2, 1967: 115mph Newport; 90mph Morrison Bridge3. November 13, 1981:100+ mph coast4. January 21, 1921: 110 kts North Head Light House5. Lewis & Clark November 22, 1805. Columbus Day-type storm?

Page 9: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

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?

Page 10: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

Wind Directions Before and After

T = 0 T + 12

Page 11: The Columbus Day Storm October 12, 1962 Has It Happened Before? Could It Happen Again? George R. Miller

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!

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

GO BEAVS!