Bulk Cliff Weather Blog: 60th Anniversary of the Northwest’s Greatest Hurricane of the Last Century: Columbus Day Storm
This Tuesday, October 12, marks the 60th anniversary of unusual Hurricane Columbus, the most intense and damaging hurricane to make landfall in the Pacific Northwest in the past century.
This blog will tell its story, describe extreme winds and damage, tell you about the quality of the forecasts, and even examine whether global warming is changing the frequency of these storms. such a storm or not.
Note: I will host a public online talk if you are interested (details later).
Campbell Hall’s bell tower in Monmouth, Oregon
The storm’s harsh nature is hard to overstate.
It spread havoc from northern California to British Columbia, with winds exceeding 100 mph in many locations and more than 130 mph in some.
It was a hurricane of the same strength as a Category 3 hurricane. But larger.
46 people died and 317 people were hospitalized. Power outage almost the entire area. Millions of trees were toppled. Flooding occurs in California. If it struck today, it would easily cause tens of billions of dollars in damage.
A bronze statue called “Circuit Rider” was toppled by the wind in Salem.
Although not a hurricane when it made landfall in the Northwest (as it was not a tropical storm), the Columbus Day hurricane started off as Hurricane Frieda in the western Pacific. This tropical storm then moved north, transforming into a moderate storm driven by temperature differences (also known as mid-latitude cyclones), and then swirling northward. entered our area on October 12 (see map below).
Some of the most intense storms to make landfall in the Northwest have begun as hurricanes: many seem to retain some of the inner core strength and substantial ambient humidity of their tropical origin.
Now, let’s take a look at some surface weather maps for the last day of the storm’s landfall (maps showing sea level pressure).
At 4 p.m. the previous day, Hurricane Columbus Day (CD) arrived in west-central California, while another (fairly strong) storm was off the coast of our area. Aesthetically, a lot of our great storms have siblings going through the days before and after.
By 10 a.m. on October 12, Hurricane CD had strengthened into a monster (with a central pressure of about 960 hPa), bringing severe rain to California and gusty winds to the northern CA and southern coasts. OR.
By 2 p.m., the lowest temperature had crossed the northwest pole of the Olympic Peninsula. By this time, strong winds had hit western Washington.
When the storm hit Oregon, its lowest pressure was about 955 hPa; Most of our deepest hurricane years are only about 980 hPa.
Equivalent to the central pressure of a Category 3 storm:
Maximum winds during the storm are shown below, provided by Dr. Wolf Read. Gusts about mph in Renton and Bellingham. 116 mph in Portland, 127 mph in Corvallis and over 135 mph on the coast.
Forecast
The day before that, this intense storm had been badly forecasted.
To demonstrate, here’s a page from the Seattle Times on October 11, which notes the forecast for a partly cloudy day inland and strong winds along the coast. Forecasters are forecasting a small coastal blow, but it’s not like the storm winds that hit the entire area.
It’s easy to see why the forecasts for that day mattered.
Those were the days before weather satellites when meteorologists received only a few reports of ships scattered across the Pacific Ocean. On the last morning alone, there were enough coastal reports that a major storm was approaching.
This is an actual surface chart created by some forecasters at the Portland Weather Bureau office at 5 a.m. on October 12
As you may know, I do weather and climate modeling/prediction as part of my day job, and I asked two of my employees (Rick Steed and David Ovens) to rerun the hurricane forecast. Hurricanes on Columbus using a modern forecasting system and at high resolution. Computer forecasting models were primitive in those ancient days – could we do better with modern tools?
The results are shown below. We were able to get an impressive storm, but not nearly as intense as it really was (about 20 hPa deeper) and with a path that was too far east to be true.
Our flawed results are not surprising: without weather satellites and other modern observation systems over the ocean, there would not be enough data to accurately describe weather conditions over Thailand. Binh Duong. Even many weather models cannot predict the weather skillfully without enough data to begin with.
Do major West Coast hurricanes have global warming intensity? It will be?
The answer seems to be no.
First, since global warming has been going on for several decades, we should be aware of some impact on hurricane strength — if there is any connection.
Here are the highest winds per year in Seattle and Portland over the past half-century. There is no evidence that the wind is increasing… in fact, it looks like a slight drop has occurred.
This trend is consistent with the assumption that we haven’t had a major Pacific hurricane in some time, with the last major event being Typhoon Hanukah Eve in 2006.
Finally, in 2015, the UW Climate Impact team completed research looked at regional climate model projections to determine whether global warming would increase maximum regional winds. This study, of which I am an author, found no increase in maximum winds in the region as the planet warms.
Number of times per year the wind hits the high wind threshold
in the area. No trend
There are reasons why strong storms in the Pacific are not increasing, including a decrease in the horizontal temperature gradient due to global warming.
My talk about the storm on Wednesday
I will be presenting the Columbus Day event on Wednesday at the department’s Dynamics/Climate workshop at 3:30 p.m. (zoom info: https://washington.zoom.us/j/99470540010)
And I recently spoke about hurricanes at the Oregon Chapter of the American Meteorological Association (found here). I was joined by Professor Wolf Read of Simon Fraser University.
