HR: 1330h
AN: AE22A-1106    [PDF]
TI: Identifying Thunderstorm Cells With LDAR Flash Initiation Points and Difficulties of Associating Lightning With Radar Cells
AU: * Demetriades, N
EM: nick.demetriades@vaisala.com
AF: Vaisala Inc., 2705 E. Medina Rd., Tucson, AZ 85706 United States
AU: Holle, R
EM: ron.holle@vaisala.com
AF: Vaisala Inc., 2705 E. Medina Rd., Tucson, AZ 85706 United States
AU: Murphy, M
EM: martin.murphy@vaisala.com
AF: Vaisala Inc., 2705 E. Medina Rd., Tucson, AZ 85706 United States
AB: Previous research has shown that cloud and cloud-to-ground (CG) lightning flashes most often occur within or slightly displaced from reflectivity cores ($>$ 40-50 dBZ). Observations from the Dallas-Fort Worth (DFW) Lightning Detection and Ranging (LDAR II) network confirm that the majority of VHF lightning sources are detected within or slightly displaced from the reflectivity cores of air mass, multicell and supercell storms and mesoscale convective systems (MCS). A statistical study using Fort Worth WSR-88D reflectivity data and LDAR II sources will be presented to summarize our observations. Since many lightning flashes extend over horizontal distances larger than a single thunderstorm cell and sometimes over 100 km (e.g. Proctor, 1983), using all VHF sources within a flash can present difficulties for identifying cells. Further research from the DFW LDAR II network has shown that the majority of lightning flashes for all storm types initiate within or close to reflectivity cores, regardless of their length of propagation. For this reason, we use the initial VHF sources within flashes to identify thunderstorm cells. The results obtained from using this method will be shown for several thunderstorm environments. In addition, comparisons will be made with the Storm Cell Identification and Tracking (SCIT) algorithm, which is based on reflectivities. The next step in this process is to associate lightning cells with their parent radar cells properly. For many thunderstorm environments this process can be extremely complex. We will illustrate some of the difficulties involved when lightning and radar identify different numbers of cells. Proctor, D.E., Lightning and precipitation in a small multicellular thunderstorm. {\it J. Geophys. Res.}, {\it 88}, 5421-5440, 1983.
DE: 3304 Atmospheric electricity
DE: 3324 Lightning
DE: 3329 Mesoscale meteorology
DE: 3394 Instruments and techniques
SC: Atmospheric and Space Electricity [AE]
MN: 2003 Fall Meeting