While searching for a topic for this week’s column I stumbled across a very interesting article published in Physics.org (phys.org). It was titled “Rising tornado warnings charts a path to improve forecasts.” It was written by Hannah Hickey from the University of Washington. There is a tornado warning protocol throughout the country, but it does have its flaws. Doppler radar does not cover every inch of the country so the famous “tornado signature” might not show up on a radar screen. There is also a lag time from when a tornado is spotted until it is reported to the authorities and the National Weather Service. A tornado warning is then issued and it can be broadcast on the weather Service’s radio warning system and local television and radio stations.
By the time the warning actually gets to you the storm has already moved significantly. According to Alex Anderson-Frey “The forecasting community is not just looking at the big, photogenic situations that will crop up in the Great Plains. We’re looking at tornadoes in regions that normally don’t get tornadoes, where by definition the vulnerability is high.” We here in the Pacific Northwest are in that latter category. It’s because we don’t see tornadoes here very often that we are caught in and area where predicting them and finding them is more difficult.
Just about 6 years ago I explained that many people have the mistaken idea that tornadoes can’t happen in Oregon. Well if you need proof stronger than past history just look back at Tuesday April 14, 2015. A small short-lived tornado touched down at about 4:10 PM on the campus of Lane Community college.
According to the LCC account: “At approximately 4:10 this afternoon witnesses reported that a funnel cloud touched down on the southwest corner of the parking lot on the main campus. The funnel cloud picked up two vehicles and moved them, flipping one of them into a center median. As soon as this was reported, an alert was issued via our campus PA system to shelter-in-place.
With my years of experience in tornado prone areas around the country and even here in the Eugene/Springfield area, the National Weather Service is usually reluctant to call it a tornado without having one of their own personnel view the site and speak with any witnesses to the event. There were two particularly credible witnesses. One was a member of the LCC Security patrol and the other was a climatologist who called the weather service to report it. Both described the scene so well and added to the way the vehicles were damaged the declaration was made.
The next day the Weather Service updated their previous statement. “000 NWUS56 KPQR 151559 LSRPQR PRELIMINARY LOCAL STORM REPORT…CORRECTED NATIONAL WEATHER SERVICE PORTLAND OR 859 AM PDT WED APR 15 2015 ..TIME… …EVENT… …CITY LOCATION… …LAT.LON… ..DATE… ….MAG…. ..COUNTY LOCATION..ST.. …SOURCE…. ..REMARKS.. 0405 PM TORNADO EUGENE 44.05N 123.11W 04/14/2015 F0 LANE OR PUBLIC AT 405 PM A SHORT DURATION TORNADO TOUCHED DOWN ON THE CAMPUS OF LANE COMMUNITY COLLEGE. A LANE COMMUNITY COLLEGE OFFICIAL WITNESSED A RAIN AND HAIL WRAPPED TORNADO THAT DAMAGED THREE VEHICLES SIGNIFICANTLY. ONE VEHICLE WAS MOVED APPROXIMATELY 125 FT AND ENDED UPSIDE DOWN ON A BERM IN THE PARKING LOT. WIND SPEEDS NEEDED TO MOVE VEHICLES NEED TO BE IN THE 65 TO 85 MPH RANGE AS A CONSERVATIVE ESTIMATE…WHICH WOULD RATE THIS AS AN EF0 TORNADO. 4/15 ) A LOT OF THE WORK THIS MORNING HAS CENTERED AROUND DETERMINING THE RATING OF YESTERDAYS EUGENE TORNADO…WHICH STRUCK A PARKING LOT OF LANE COMMUNITY COLLEGE AND OVERTURNED A FEW VEHICLES. GIVEN THAT THERE WAS NO DAMAGE TO OTHER STRUCTURES…AND THE WIND SPEEDS REQUIRED TO LIFT VEHICLES ARE SOMEWHAT OF AN UNKNOWN AND EVOLVING AREA OF RESEARCH…THE STORM PREDICTION CENTER RECOMMENDED AN EF-U RATING…THE U STANDING FOR UNKNOWN. SINCE THERE IS NO EXISTING NWS DIRECTIVE AT THIS POINT WHICH SUPPORTS AN OFFICIAL EF-U RATING…THE RECOMMENDATION WAS TO RATE IT AN EF-0…AS NO DAMAGE TO OTHER STRUCTURES WAS FOUND NOR REPORTED. WEAGLE”
n previous article from April 4, 2014 called Dorothy Couldn’t Get To OZ With One. I explained, in very basic terms, how tornadoes form. The first description explains tornadoes in the Midwest and elsewhere, but not here in Oregon. In this state I said we average about 3 tornadoes per year over recorded history. The Midwest tornadoes form when the hot humid air rises high up into the atmosphere where the air is colder. The higher that air raises the stronger the tornado can be. This is why we have what are termed “cold core” tornadoes here. The cold air has to drop down to meet the warmer air which just doesn’t reach up far enough. That makes a weaker funnel which usually spends about 10 minutes or so on the ground and does very little damage.
You might remember back in 1996 a small tornado dropped down in the Gateway area damaging and moving a shed. The National Weather Service in Portland sent one of their meteorologists here to check it out. Our National Weather Service Office in Eugene was still in operation, but closing soon, and the last remaining meteorologist also examined the site. If I remember correctly the Portland report was that it was not a tornado because there was no drag mark on the ground.The Eugene report said it was a tornado due to the angle of the damage and eyewitness reports. Proving what causes this kind of damage is not as simple as you might think.
The last time I checked the statistical information not one person has ever been reported to die in Oregon as a direct result of a tornado. Don’t get too cocky about that because the odds may be against having one, but if it hits you I don’t think you’ll think it’s such a rare event. If you see one or a tornado warning is issued by the authorities take shelter immediately in an interior room with no windows and a narrow roof line. A good example is a closet. Get down on the floor, cover your head and hug the wall until it is over.
Let’s hope the researchers can help give us better ways to access the risk factors involved and produce better and more accurate warnings in the very near future.
Let me know what you would like me to talk about or explain. You can comment below or email me at: [email protected].