This post focuses on tornado statistics in the Tri-Cities and Columbia Basin. For specific details about the Richland tornado that happened on March 31, head over to this AgWeatherNet article that I contributed to.

Tornadoes are a rare occurrence in the Columbia Basin, but they aren’t unheard of. This is something that we were reminded of on Tuesday afternoon when a small tornado touched down on the north side of Richland. But just how often do we get them?

WASHINGTON & OREGON

To start off, I want to brush over statewide climatology for both Washington and Oregon. Both states experience an average of three tornadoes annually, and the vast majority of these are quite small. Just because each state has an average of three per year doesn’t mean that there are actually tornadoes every year. Averages are a fickle thing when it comes to this, especially when our average is this low. The last time Washington had a year without a reported tornado was 2012, and for Oregon it was 2014.

On the other hand, some years have many more tornadoes than the annual average. Since 1950, the year Washington saw the most tornadoes was 1997 with a grand total of 12. That year even had what we could arguably call a tornado outbreak, with four occurring on May 31. These were all over the state, with touchdowns near Spokane, Tacoma, and Vancouver. That year was also the winner for Oregon with 14 confirmed tornadoes. Interestingly, only one of these came on May 31.

Like I said, most of these tornadoes are weak. For a tornado to be considered strong, it must be rated as an EF-2 or above. This means that National Weather Service meteorologists who go to survey the damage have to determine that winds reached 111 mph or higher. In Oregon, this has only happened five times. Washington has had a few more strong tornadoes, reaching up to 16 since 1950.

In both states, the strongest tornadoes ever recorded were F-3 (not EF-3, because this happened when we still used the Fujita scale rather than the Enhanced Fujita scale). Washington has had three of these, but Oregon has only had one. The most damaging of these struck in 1972, hitting Portland before crossing the Columbia into Vancouver. Six people died that day and 301 were injured. In today’s dollars, damage was around $18 million to $30 million.

LOWER COLUMBIA BASIN

Washington and Oregon are both big states, though. Tornadoes that happen in the Portland-area are certainly interesting, but don’t help to give us a picture of what happens here. For the purposes of this section, we’ll be looking at data for Benton, Franklin, and Walla Walla Counties in Washington as well as Morrow and Umatilla Counties in Oregon.

Only one tornado reached to F-2 strength (again before the EF scale came into use). This struck the Wallula area in 1958 and didn’t cause any damage. This is the largest tornado on record for our area. May is the month when we’ve seen the most touchdowns, but our tornado season (if you can call it that) lasts from April to July.

In comparison to the 1972 Portland-Vancouver tornado, the cost of damage from any one tornado around here has only reached up to $50,000. That was from an EF-1 that struck the Umatilla Indian Reservation outside Pendleton causing damage to a few buildings. Part of why damage is so infrequent from tornadoes here is because of how rural we are. The 1972 tornado only caused so much damage because it went straight through an urban area, and we could expect something similar if a tornado that large happened to impact developed areas in and around cities in the Columbia Basin.

There is an old myth that the reason tornadoes don’t strike cities as often is because the buildings somehow steer a tornado away or cause it to dissipate. This has been proven to be false, and there are numerous examples of tornadoes even hitting downtown areas of major cities like Baltimore, Fort Worth and Ottawa. Even cities in the west are not immune. A prime example of this is the tornado that tore through downtown Salt Lake in 1999.

Instead of that myth, consider throwing darts at a map. Cities cover such a small area that unless you were practiced at throwing darts, your odds of hitting a city instead of a rural area are slim – even if you’re aiming for one. Of course, in this analogy more darts are being thrown at a map of Kansas than Washington or Oregon, so cities in Kansas will be hit more often.

Before the March 31 tornado, the most recent tornado to strike the area was an EF-0 that hit near the Kennewick Fred Meyer in 2016. This one left a damage track that was around 800 feet long and 300 feet wide. Even though this was rated at the weakest point on the Enhanced Fujita scale, it caused $20,000 in property damage along Morain between 7th and 10th. This again demonstrates that even here, we are vulnerable to tornado damage.

Nearly every time we have a major wind event, I see someone on Facebook trying to tell people it was a tornado. Often times, this is false. Yes, tornadoes happen here, but most wind damage comes from non-tornadic regional wind storms that we get in the fall and winter. If you want to know if something was a tornado, feel free to reach out to me through Tri-Cities Weather or to our local National Weather Service office.

DATA LIMITATIONS

As with all datasets, there are limitations to what we can determine. In our case, our biggest limitation is a lack of data. Consistent tornado records have only been kept in the United States since 1950, and during that time period only 18 tornadoes were confirmed to have struck in the Lower Columbia Basin. When looking at these data, it’s hard to determine what is an actual trend and what is just static.

A prime example of this is the March 31 tornado in Richland. Previous to that one, there was not an example on record of a tornado in any of the five counties mentioned above in March. While only six months out of the year have a recorded tornado touchdown in our area, I would wager that if we had a thousand years’ worth of data rather than 70 we would find tornadoes can happen any time of the year. That said, like I mentioned above, it definitely seems that our most likely time to see a tornado is April through July.

If we had a lot more data we would find that, while incredibly rare, tornadoes larger than an EF-2 are certainly possible here. An unusually strong severe thunderstorm in 1995 dropped hail larger than baseballs in Hermiston. This thunderstorm was very reminiscent of large thunderstorms on the Great Plains, with a long hail damage track that ran from the east slopes of the Cascades all the way through and beyond Hermiston. I would not be surprised to find that, just like infrequent large hail events, incredibly infrequent large and damaging tornadoes are possible in the Columbia Basin.

Also on the topic of a lack of data – our area has quite a low population with very few people providing storm reports to the National Weather Service. Modern technology, especially cell phones, has allowed the NWS in Pendleton to receive more frequent and thorough reports than in years past, but I always believe that the more good data we can get the better. Consider becoming certified as a storm spotter by the National Weather Service. Because of COVID-19, all of the spotter training courses will be held online. More details about that can be found at this link.

TORNADO SAFETY

Life-threatening tornadoes do happen in the Columbia Basin, and it is important that you know what to do if a tornado warning is issued. The most ideal place to be would be a basement room with no windows or outward facing walls. Many people don’t have access to this, so just remember to go to the lowest level of a building, preferably in a room with no outward facing doors, windows, or walls. If all of the rooms have an outward facing area, just try to get to a central location. When you have reached that spot, crouch down facing an interior wall and place your hands over your neck and head to protect them. This part is similar to in an earthquake drill.

If you can’t get to a building, lie down in a ditch or other low spot away from trees and cover your neck and head. You want to make yourself as low as you can. You absolutely do not want to be in a car during a tornado, as they can be tossed pretty easily. Also make sure to not shelter under overpasses. With how these are built, they often become wind tunnels that amplify the tornado’s wind.

Tornado warnings issued by the National Weather Service are automatically pushed to all mobile phones within the county that the warning is in. Here in the West, our counties are massive, it is unlikely that a tornado warning will cover the entirety of the county you are in. The first thing to do when you receive this message is to go to your safe location. Once there, you can check the National Weather Service’s website to see if you are indeed in the warning area or not. If not, feel free to leave your safe place, but keep an eye on the weather situation around you.

It is important to be able to find yourself on a map. Our phones have made navigation a breeze, but they have also made it so that many people do not have a good idea of where they live, work, or hang out. Take some time to study a map to learn where you are. This is also something you should consider doing if you are traveling. Natural disasters definitely don’t happen everywhere every day, but in the event that one does happen knowing where you are can be a great asset.

Finally, another line of defense for all sorts of damaging weather is an SAME enabled NOAA Weather Radio. The federal government has radio stations all over the country that broadcast automated weather information from the National Weather Service. When they issue weather advisories, watches, and warnings, a weather radio is one of the first places that will receive it. SAME technology goes a step further, allowing you to enter a specific code for your county (for example Benton County is 053005). When a weather alert is issued for the county you typed in, your weather radio can automatically alert you. Many weather radios even allow you to set up so that it will only alert you for specific warnings (so, for example, you could set it for only tornado warnings). These may seem like old technology, but they can be pretty handy in situations like if cell phone towers are overloaded. If you have questions about weather radios, including how to set them up, please don’t hesitate to reach out to me through Tri-Cities Weather on Facebook.

Remember, the time to prepare is before a potential event, not during. This goes for anything – tornadoes, wildfires, floods, etc. It’s better to be prepared for something that never comes than for it to come and catch you unprepared.

Most of the data for this post came from the Storm Events Database maintained by the National Centers for Environmental Information.