Tornadoes in Texas are one thing, but I read an interesting story with photos on KTVZ.com about Connie Robbins who believed she had driven through a possible tornado in eastern Oregon Tuesday. According to the article, the D.O.T. thought the damage was tornadic, but the National Weather Service initially said that they believed it was high winds "until they examined the evidence." Afterwards, they reported it was an EF-1 tornado, then changed back to straight-line winds (you can read both reports here). Over 50 power poles were broken and some outbuildings in the area were partially destroyed.

Tornadoes are rare in eastern Oregon -- the National Climatic Data Center's database (I used to work there), which is the official record, says that only 5 have occurred, all of "F0" strength, in Harney County since 1950 (and the county is huge, covering over 10,000 square miles). I interviewed Connie about her experience and frustration with the NWS Boise office changing their minds on what they thought the damage might be. KTVZ.com reported - screenshot via Google below - that the NWS said it was a tornado then later changed their story text and headline to switch to wind. This makes me a little uncomfortable and is a bit different than the practice of Bloggers, where they don't change the story but create an additional story or publish changes bottom to top, but some TV and newspapers still attempt to change the permanent record.

Ultimately I think she was also disappointed that their final decision was wind; but as I've said before, people should never be disappointed that something they witness is ruled straight-line winds. Thunderstorm downbursts frequently do as much damage as weak tornadoes and can demolish trees and buildings; tornadoes only add twisting, sometimes higher, winds.

The radar above from AccuWeather.com shows a map just after she drove into the high winds (she was between Burns and Crane). Unfortunately, this just shows the shape of the heavy rain within the storm high in the atmosphere. It does show a bow shape, which typically indicates high straight-line winds, especially in the middle, which was probably where she was as it moved north over her. Looking at her photos, I'm not surprised to see a "gust front" bowing out from the storm.

Successful storm surveys depend on two things: Damage analysis and radar data. Connie pointed out that there was very little on that stretch of road to damage. Another piece of the puzzle that was not available to this storm survey that could have made the decision easier, was radar wind data. The area around Burns, Oregon (shown as an "X" in the image below) is in one of the four major "radar holes" in the West. The storm was barely on the Boise, Idaho radar scope and at that distance the beam would have been about 15,000 feet above the ground -- of little use for analysis of what was going on where Connie was.

When viewed close-up or from the side, a gust front can appear to be a funnel shape coming down from the sky, especially if there are multiple fronts (a great example is shown here) and "scud" clouds rising up in front of it can also fool the human eye into thinking that it just spied a funnel cloud.

I usually believe the NWS when they do a storm survey, as a meteorologist who has done storm surveys before. And if it's true that two reports were false (one of which they explained in the article, another that they didn't) then I can understand why they said tornado initially then switched it. But they are still hedging their bets a little with the final report saying that there could have been a (coincidental) funnel cloud separate from the winds that caused the damage. In truth, we'll never know for sure but what little radar and damage info we have. However with the photos that are shown in the article, I see a lot more evidence for straight-line downburst winds than a tornado (the last picture in the article even looks like our illustration below, showing how downburst winds charge out of a thunderstorm an spread out as they hit the ground).

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