MCVs are fairly common in the central US during the warm season, so it may seem weird that I'm starting a thread for this one. I'm doing so because this particular one seems very well-defined and large, and the availability of satellite and radar data make it easier to document.
A strong and well-defined MCV developed from the large MCS that occurred in the Plains last night. The development of this MCV can be seen in radar loops as a curl in the reflectivity. It originated in the back of the stratiform region of the MCS, most specifically around Harper Co., OK and near the KS-OK border generally between 0500 and 0600 UTC.
The MCV is also apparent on satellite. The cyclonic rotation is not visible on water vapor or IR until this afternoon when the higher clouds clear out, but the associated upper-level negative vorticity and divergence give it away.
Cotton and McAnelly have authored many papers on the development and evolution of MCSs, MCCs, and MCVs, and describe the development of MCVs as resulting from mid-level convergence associated with the immense latent heating from all of the convection and the upward motion and corresponding upper-level divergence. If this persists long enough, the Coriolis force begins to do its work and the convergent winds at mid-levels and divergent winds aloft begin curving, hence developing the rotation associated with MCVs. MCVs are usually too small to be captured in the rawinsonde network. However, this one appears to be large enough to show up, as seen in the 12Z 500 mb and 200 mb analyses (see the TOP, OAX, LBF, and DDC sounding locations to see the circulation). MCVs can persist for a long time and present favorable conditions for the genesis of other MCVs, especially in low-shear, weak-flow environments near ridges, which is a fairly common UA configuration in the Central US during the summer.
The development of the MCV was also captured in the SPC mesoanalyses:
Note: thanks to Tim Supinie and Greg Blumberg for the inspiration to post this.
A strong and well-defined MCV developed from the large MCS that occurred in the Plains last night. The development of this MCV can be seen in radar loops as a curl in the reflectivity. It originated in the back of the stratiform region of the MCS, most specifically around Harper Co., OK and near the KS-OK border generally between 0500 and 0600 UTC.
The MCV is also apparent on satellite. The cyclonic rotation is not visible on water vapor or IR until this afternoon when the higher clouds clear out, but the associated upper-level negative vorticity and divergence give it away.
Cotton and McAnelly have authored many papers on the development and evolution of MCSs, MCCs, and MCVs, and describe the development of MCVs as resulting from mid-level convergence associated with the immense latent heating from all of the convection and the upward motion and corresponding upper-level divergence. If this persists long enough, the Coriolis force begins to do its work and the convergent winds at mid-levels and divergent winds aloft begin curving, hence developing the rotation associated with MCVs. MCVs are usually too small to be captured in the rawinsonde network. However, this one appears to be large enough to show up, as seen in the 12Z 500 mb and 200 mb analyses (see the TOP, OAX, LBF, and DDC sounding locations to see the circulation). MCVs can persist for a long time and present favorable conditions for the genesis of other MCVs, especially in low-shear, weak-flow environments near ridges, which is a fairly common UA configuration in the Central US during the summer.
The development of the MCV was also captured in the SPC mesoanalyses:
Note: thanks to Tim Supinie and Greg Blumberg for the inspiration to post this.
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