What an active storm day this was! Nationally, dozens of tornadoes marked a “Corn Belt outbreak” from Colorado to the Ohio Valley, including a deadly and very destructive one that night near Dayton, OH. Personally I saw four supercells and at least three tornadoes in northeastern Colorado, between Denver and the inner corner of Nebraska. The adventure began with this midday beauty: a low-topped, high-based, strongly tilted supercell that evolved from a chimney-like band of towers percolating off the Palmer Divide, just southeast of Denver. This “tail-end Charlie” storm, located north of Strasburg at the time, emerged from the mess and took over for about an hour. The storm constantly fought its own outflow, whose surface temperature we measured at 51 degrees F in Bennett. In the process it offered a marvelously fluid, skeletal whole-storm cloud display. A deep moat of cold, rear-flank outflow was marked by the sunlit scud that was moving left to right in front of the mesocyclone updraft at lower middle. The basal wall cloud rotated obviously but not intensely. From here northward, we spotted a few gustnadoes in front of the mesocyclone and wall cloud (in the wrapping outflow) that easily could have been misconstrued for tornadoes beneath, by an impatient or inexperienced spotter. Ample sunlight shone in from south of the storm, thanks to its early timing, offering an unusual and wonderful lighting perspective for a Great Plains supercell observer.
2 NNE Byers CO (27 May 19) Looking NW
39.7403, -104.2097Midday Colorado Supercell
What an active storm day this was! Nationally, dozens of tornadoes marked a “Corn Belt outbreak” from Colorado to the Ohio Valley, including a deadly and very destructive one that night near Dayton, OH. Personally I saw four supercells and at least three tornadoes in northeastern Colorado, between Denver and the inner corner of Nebraska. The adventure began with this midday beauty: a low-topped, high-based, strongly tilted supercell that evolved from a chimney-like band of towers percolating off the Palmer Divide, just southeast of Denver. This “tail-end Charlie” storm, located north of Strasburg at the time, emerged from the mess and took over for about an hour. The storm constantly fought its own outflow, whose surface temperature we measured at 51 degrees F in Bennett. In the process it offered a marvelously fluid, skeletal whole-storm cloud display. A deep moat of cold, rear-flank outflow was marked by the sunlit scud that was moving left to right in front of the mesocyclone updraft at lower middle. The basal wall cloud rotated obviously but not intensely. From here northward, we spotted a few gustnadoes in front of the mesocyclone and wall cloud (in the wrapping outflow) that easily could have been misconstrued for tornadoes beneath, by an impatient or inexperienced spotter. Ample sunlight shone in from south of the storm, thanks to its early timing, offering an unusual and wonderful lighting perspective for a Great Plains supercell observer.
2 NNE Byers CO (27 May 19) Looking NW
39.7403, -104.2097