By Steve Pierce President, Oregon Chapter of the American Meteorological Society
The Vancouver tornado of 1972 stands alone in the record books. It is the holy grail of Pacific Northwest tornadoes. Even now, 40 years later, the April 5th 1972 Vancouver tornado is the single deadliest tornado to strike west of the Rocky Mountains in modern history, killing six people and injuring more than 300 in Vancouver, Washington alone. Those who lived through that day witnessed the fury of mother nature to a degree that is not likely to be matched again anytime soon. The 1972 tornado was similar in atmospheric structure to that of the Hazel Dell tornado of January 2008. However, the 1972 tornado was much stronger. The 2008 Hazel Dell tornado was an EF1 on the newer Enhanced Fujita scale that became operational in 2007. Winds were likely between 90-110 MPH in the 2008 Hazel Dell tornado. The Vancouver tornado of 1972 was rated an F3 under the original Fujita scale which came online in 1971. Winds on the older Fujita scale were estimated between 158–206 MPH if rated as an F3, as was the case in the Vancouver tornado of 1972.
Unlike tornados east of the Rockies, tornados in the Pacific Northwest are referred to by many as "cold core" due to their lack of humid and buoyant air. The Pacific ocean keeps our atmosphere relatively mild year round. This is not conducive for the formation of super cell thunderstorms needed to generate the really large and damaging tornados you might see in the Midwest. What makes the 1972 tornado so rare is the fact that it was able to spin up to F3 status and stay on the ground for nearly 8 miles.
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