Gravity Wave cloud formations (a true but misleading and harder to understand term, even when you have a real meteorologist to talk with about it) happen here all the time. At the surface, even with a high quality digital output barometer I've never seen any fluctuations to measure, so I'm lead to believe that the variations in pressure are pretty tiny.
Nonetheless, as the article and Farmtalk point out, the flat out admitted that they didn't know what caused this for sure.
Why not just call it a downdraft, or a straight line wind gust or whatever?
I'm skeptical it has to have a mysterious cause and was just a wind gust.