A Comparison of Misovortices Found Within Two Long Lake-Axis-Parallel Lake-effect Snow Bands during the OWLeS Project

Using Doppler on Wheels (DOW) data collected during the Ontario Winter Lake-effect Systems (OWLeS) project, dual-Doppler analysis was conducted of the long lake-axis-parallel (LLAP) band that occurred on 9 January 2014. This analysis indicated the existence of a string of misovortices along the southern edge of a west-to-east LLAP band. A similar case occurred on 7 January 2014 during OWLeS in which a string of misovortices was found on the northern edge of a west-to-east LLAP band. The difference in location of these misovortices, with respect to the center of the band, is suspected to be caused by the proximity of the band to the northern/southern Lake Ontario shoreline. During both events the misovortices were located near the strongest horizontal gradient in reflectivity and along a cyclonic shear zone. The average diameter of the misovortices found during the 9 January case was between 2.5 - 4.5 km, which was larger than those present in the 7 January event. In addition, the average horizontal spacing between the misovortices during the 9 January case was 5.25 km, which was less than that of the 7 January event at 7.4 km. This difference in spacing was likely related to the frequent interactions between the misovortices during the 9 January case, thus creating discrete groups of interacting vortices. The average horizontal spacing within these groups of misovortices was found to be 3.5-4 km. Additionally, the vertical vorticity values of the vortices which occurred on 9 January ranged between 6.2 - 10.5 x 10^-3 s^-1, whereas the vertical vorticity values during 7 January ranged from 1.0 - 3.0 x 10^-2 s^-1. Thus, it was found that the LLAP band occurring on 9 January contained larger, yet weaker misovortices than those present in the 7 January event. In addition, with regards exclusively to the 9 January case, the misovortices exhibited frequent interactions within discrete groups. Although the proximity of the shoreline is suspected to influence the location of the misovortices with respect to the center of the band, it is currently unknown to what extent. Therefore, future work includes further investigating the location of misovortices present within other LLAP bands that occurred during OWLeS.