Equipped with a new home PC, I”ve at last found myself with the processing power to handle a radar software item I”ve been drooling over ever since I heard of it and saw what it can do. Last Sunday I finally purchased Gibson Ridge”s powerful GR2AE (the AE stands for “Analyst Edition”). Given my tight budget these days, it wasn”t an economical move; it was, however, an inevitable one–and, as it turned out, a timely one.\r\n\r\nThe next day, April 28, I began tinkering with the program. It”s quite amazing, featuring as its crown jewel a volume explorer that crunches together all the scans of a storm and displays them as a three-dimensional image. The result is like an X-ray of a thunderstorm that you can view from nearly every angle, flipping it around at whim with your mouse.\r\n\r\nOf course, you need a storm to work with, so I went off in search of one. Gibson Ridge radar products make that process a snap with a window that shows current warnings. I clicked it on, not expecting much, hoping for just a garden-variety thunderstorm to help me acquaint myself with the new software. Instead…whoa! Four tornado warnings, three for Virginia and one for North Carolina. I knew the Storm Prediction Center had issued a slight risk for that area, but I never expected anything to actually come of it. Not that tornadoes don”t occur on the East Coast, but they”re infrequent. The region isn”t exactly Tornado Alley.\r\n\r\nThis day was an exception. There they were: four discrete supercells lighting up the radar screen, raking paths across the East ahead of a squall line. The northernmost storm–the largest of the lot, and seemingly the most robust–had a broad area of rotation. After a number of scans, the radar suddenly produced an intense couplet, indicating a swift intensification of that rotation.\r\n\r\nSelecting the area of interest, I activated the volume explorer. I now was getting a look at the storm”s intestines, so to speak–at precipitation intensities and basic wind-flow patterns that I could examine from a multitude of vantage points.\r\n\r\nBear in mind, now, that I”m brand-new to GR2AE, and my skill with it is rudimentary. Nevertheless, as I followed the storm”s progress, I could tell that the rotation was tightening and appeared to be lowering as the storm made a beeline for Suffolk, Virgina. I wasn”t sure what was happening out there at ground level, but I sensed that a tornado was either immanent or already in progress. So, deciding to try another first, I saved an image.\r\n\r\nHere it is:\r\n\r\n
\r\n\r\nNote the reddish tube on the right side of the image that looks something like an upside-down funnel, with a somewhat brighter shade of green just to its left,\r\nlike an aura. This is the mesocyclone. I won”t go so far as to say you can see the actual tornado, as radar normally isn”t able to depict tornadoes, but I can”t rule out the possibility. The funnel moved through an urban area and conceivably lofted enough debris to be detected by radar. Regardless, the image gives you a fair idea of the storm”s structure at the time it was going tornadic. Not a bad catch for a newbie!\r\n\r\nI welcome comments, particularly from chasers and meteorologists more knowledgeable than I.
