Thursday, March 11, 2010

March 10, 2010 - OK/KS low-topped convection




I ventured out with Derek Deroche and Jared Leighton with an initial target near Independence, KS. We shifted our target southwest by 50 miles by early afternoon as it appeared the surface low’s progression was a little slower than anticipated. Jumped on a region of persistent low-topped convection located ENE of the sfc low south of Ponca City by mid afternoon. For the most part, low-level structure appeared fairly benign from our vantage point east of Burbank, OK.

We followed it northward on a rough dirt road to Foraker, then up Hwy 18 to Grainola. As we approached the KS/OK border, we noted a new stout updraft developing along the trailing line of arcing convection, immediately next to the mature tower. As this vertically grew, we observed a well-defined funnel cloud develop underneath the updraft base, associated with the new robust convection just SE of Cedar Vale, KS. This feature persisted for less than one minute before dissipating. From the existing sfc obs, we inferred this tower was in close proximity to the sfc warm frontal boundary draped across SE KS. Thereafter, we made several passes through hail swaths, with the biggest stones near a quarter. We stopped to enjoy the low-topped convection prior to sunset north of Sedan, KS and called it a day.

-SFB