Electric Charging In Comma-Head Regions of Continental Winter Cyclones

This manuscript contains an analysis of the storm structures that caused a charging response at the surface in the winter storms of 24 NOV 2009 and 9 DEC 2009. An electric field mill (EFM) was used to determine the nature of the changes in the surface electric field. A vertically-pointing radar analyzed the structures in the bands passing overhead. In the 24 NOV 2009 cyclone, 4 strokes occurred near the EFM. In the 9 DEC 2009 cyclone, charge fluctuations occurred with band passages, but there was no lightning. Furthermore, a climatology of 22 winter cyclones over four winter seasons was developed to determine the locations of lightning strokes in the comma-head regions of those cyclones. The storms were grouped based on the mean location within the comma-head of most of the lightning. The climatology showed that 16 of the cyclones had most of their lightning in the equatorial/southern region of the comma-head, with most of the lightning occurring with dry slot convection, or along the interface between the dry slot and the comma-head. When lightning occurred further north, it was comparatively infrequent and isolated.