These were exactly my thoughts. It's rare to have rain without wind. Even a mild breeze would distort the shape of the 'umbrella'. Strong winds would require it be pointed into the wind as with any umbrella, however without a rigid structure the air curtain would virtually collapse flat providing no protection whatsoever.<p>To work in all weather this umbrella would have to be able to manipulate its output from virtually perpendicular to the shaft to parallel.<p>Honestly, this might work with compressed air, but that itself would present serious problems; you'd likely only be able to charge it once a day and the cylinder would be heavy, but perhaps not as heavy as the original design. It would also enable the umbrella to have a shaft similar in appearance to a regular umbrella.