This scene was every bit the chaotic, mysterious convective mess that it looks! About half an hour after staring downhill into the notch of a line-embedded supercell, the storm accelerated east-northeast. Here, its dense, rain-wrapped main mesocyclone lurked to the right, while small but intense updrafts developed over the rear-flank gust front across most of this view. A complicating factor: the updrafts were rotating, some briefly but rapidly, and this entire section of the rear flank was a well-defined cyclonic-shear zone. While long-lived or significant tornadoes are very unlikely in this scenario, a brief spinup couldn’t be ruled out, and the whole area warranted close scrutiny. Another complication: the terrain was slightly higher to my north, obscuring true ground beneath it all. Another complication: scud tags rise, apparently right off the ground, in the rain-cooled air behind the gust front and updrafts, forming a rampart of tornado look-alikes. Some of those appeared to be slowly turning or converging. It all challenged this deeply experienced storm observer’s spotting skills as few situations have. A final complication: my continued eastward progress to the next, rather distant paved north option would have to be on a deteriorating, already unpaved road.
Two options presented themselves here: stay abeam of this closer, horrendously messy, outflow-surfing, line-embedded supercell regardless, and hope to catch a brief, low-odds spinup somewhere in the murk, or zigzag south-southeast about 60 miles to the projected track of a new, discrete cell to the south. Sometimes the decision to leave doesn’t work; however, in this case, the reasoned gamble paid off.
8 SW Fleming CO (27 May 19) Looking NNW
40.5842, -102.9253Downdrafts, Updrafts, Chaos!
This scene was every bit the chaotic, mysterious convective mess that it looks! About half an hour after staring downhill into the notch of a line-embedded supercell, the storm accelerated east-northeast. Here, its dense, rain-wrapped main mesocyclone lurked to the right, while small but intense updrafts developed over the rear-flank gust front across most of this view. A complicating factor: the updrafts were rotating, some briefly but rapidly, and this entire section of the rear flank was a well-defined cyclonic-shear zone. While long-lived or significant tornadoes are very unlikely in this scenario, a brief spinup couldn’t be ruled out, and the whole area warranted close scrutiny. Another complication: the terrain was slightly higher to my north, obscuring true ground beneath it all. Another complication: scud tags rise, apparently right off the ground, in the rain-cooled air behind the gust front and updrafts, forming a rampart of tornado look-alikes. Some of those appeared to be slowly turning or converging. It all challenged this deeply experienced storm observer’s spotting skills as few situations have. A final complication: my continued eastward progress to the next, rather distant paved north option would have to be on a deteriorating, already unpaved road.
Two options presented themselves here: stay abeam of this closer, horrendously messy, outflow-surfing, line-embedded supercell regardless, and hope to catch a brief, low-odds spinup somewhere in the murk, or zigzag south-southeast about 60 miles to the projected track of a new, discrete cell to the south. Sometimes the decision to leave doesn’t work; however, in this case, the reasoned gamble paid off.
8 SW Fleming CO (27 May 19) Looking NNW
40.5842, -102.9253