Curitiba Dark Storm
February 21, 2008
At first glance, this photo seems to be only a simple shot taken at night of the distant city of Curitiba, in southern Brazil. But this photo was actually taken at 6:19 p.m. local time on October 29, 2007, more than an hour before sunset! A huge, severe storm produced clouds so massive that the day turned into night in a matter of minutes. I've never seen such a dark storm! Before this storm hit, strong convergence and wind sheer was evident as low level clouds scurried off in the direction of the western horizon, from where the storm was rapidly approaching. This perhaps contributed to exceptional vertical development -- air was forced upward along the convergence line. In general, the higher the storm clouds, the darker the surface.