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A Typical Normal Pacific Northwest Wind Storm
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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.
A Typical Normal Pacific Northwest Wind Storm
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
Paths of Columbus Day-Type Storms
With the low center off Northern California
T = 0
When Low Center is Off NW Washington
T + 12
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?
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?
Wind Directions Before and After
T = 0 T + 12
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!
GO BEAVS!