NOTE:Numbers after certain sentences indicate the photo being referred to.
Scott Blair and I targeted southwest Oklahoma on this day and set up near Duke around 2 p.m. We waited for storms to fire along the dryline, noticeable on Scott's morning dewpoint analysis,1 and observed towering cumulus develop, lean from the shear, and bump against the cap before weakening.2 Finally, around 3:30 p.m. one tower broke the cap and began organizing. Jeff Lawson, a chaser from Denton, Texas, joined up with us while we observed the storm. The storm had explosive convective development and quickly became a full-blown supercell 3 with a noticeable mesocyclone.4 After taking Hwy. 19 east to track the cell, we pulled off near Roosevelt and watched a new meso form and occlude to our west 5 while the old meso to our north developed an inflow tail, the type that resembles a funnel or tornado and is probably commonly reported as such.6 The RFD became noticeable and quickly wrapped around the old meso 7 and a low-contrast funnel formed.8 We continued east on Hwy. 19, and watched as the meso to our north continued to wrap up with impressive rotation and a sustained funnel.9 The supercell characteristics of the Roosevelt storm are noticeable in the radar reflectivity image, which shows a hook and inflow notch.10 The velocity image also shows a well-defined couplet with the cell.11 After losing the cell in the Wichita Mountains, we dropped south into Texas and the warm sector. A call to nowcaster Phillip Flory, who did a fanatastic job throughout the day, and seeing a radar image 12 during a data stop in Wichita Falls, Texas, convinced us to go after a left-moving supercell that formed after a supercell split. Notice how the storms in the radar image are almost mirror images of each other. After a supercell splits, the northern portion of the cell rotates anticyclonically while the southern cell remains cyclonic. We took Hwy. 82 out of Wichita Falls to intercept the anticyclonic storm since it was closer and moving north-northeast toward us. After noticing the colors being produced by the setting sun, we decided to pull off near Mabelle to observe the cells, which were now beginning to die. The mammatus on the southern cell's anvil began lighting up 13, and the anticyclonic cell glowed a brilliant orange.14; 15 This was a beautiful way to cap off the chase, which, up to this point, has been the best of the year.
Mesocyclone Video Capture (Picture #9): Courtesy of Scott Blair