Chapter VIII: Summary
Table of Contents
- Summary
Chapter VIII
The synoptic setting was favorable for triggering deep convection due to moderate-to-high buoyancy, wind shear and large-scale convergence detected in the airmass where the thunderstorm was formed. Some parameters even indicated the possibility of severe storms (strong downdrafts, eventually supercells). The ECMWF model analyses and WV satellite imagery reveals the presence of dry mid- and upper air, which could enhance the downdrafts and the intensity of the outflows. This could be diagnosed even by simple indices such as TED (used in combination with GOES satellite imagery) or DTHETAE2 – tested also in the frame of GII (Simon et al., 2011). Preliminary results of high resolution simulations (WRF) are consistent with this concept and show that intrusion of dry air to the rear of the thunderstorm, intensification of downdrafts, and, eventually, development of rear-inflow-jets (indicated also by radar imagery) could have produced very strong out-flowing winds. More frequent (1-5 min) outputs and more detailed diagnostics would be necessary to specify the storm structure and dynamics.
Satellite data provide information on the atmospheric instability and water vapor content, confirming the presence of warm and moist air in the investigated area. Products such as Convective Initiation and NWCSAF RDT gave a very good indication of the early development of the studied convective cells. In the mature phase the radar features (bow echo) and satellite cloud top features (intense overshooting tops, cold ring features, intense gravity waves, ice plumes) indicate high probability of storm severity.
Rererences:
- Ellrod, G.P., Nelson III, J.P., Witiw, M.R., Bottos, L., Roeder, W.P., 2000. Experimental GOES sounder products for the assessment of downburst potential. Wea. Forecasting 15, 527–542
- Skamarock, W.C., Lindsey, D.T., Dudhia, J., Gill, D.O., Barker, D.M., Duda, M.G., Huang, X.-Y., Wang, W., Powers, J.G., 2008. A Description of the Advanced Research WRF Version 3. NCAR Technical note NCAR/TN-475+STR. June 2008, 113 pp.
- Simon, A., Kanak, J., Sokol, A., Putsay, M., Uhrinova, L., Csirmaz, K., Okon, L., Habrovsky, R., 2011. Case study of a severe windstorm over Slovakia and Hungary on 25 June 2008. Atmos. Res., 100, 705-739.
- L. Delobbe, S. Dewitte, N. Clerbaux (2011): Rapport situation météo Pukkelpop 18/08/2011