Severe convective supercell outbreak over western Bulgaria on July 8, 2014 (original) (raw)

Abstract

⎯ Bulgaria is situated in a geographical area with high frequency and intensity of thunderstorms and hail events. Like in many other countries, an upward trend of weatherinduced damage has been observed during the last 15 years in Bulgaria. Much of it was caused by extreme weather events such as torrential precipitation associated with severe thunderstorms or/and wind storms. The series of flash floods and extreme hail storms, which hit Bulgaria in the warm half of 2014, were in line with that trend. On July 8, 2014, three supercell storms developed over West Bulgaria and heavily impacted urban areas in the afternoon. The extremely strong hail storms over Sofia and Montana were accompanied by strong wind gusts (about 85 km h-1) and torrential rain. The giant hail stones in Sofia had diameter of up to 10 cm and irregular shape. The severe hail and rain, and very strong wind caused substantial damage to infrastructure, buildings, vehicles, and agriculture. More than 40 people were injured by hail stones or collaterally by broken windows. One man was killed by a fallen tree. In Sofia alone, the reported damage was worth more than 100 million euro according to data from insurance companies. The paper presents the analysis of the evolution of the convective clouds based on radar data. The Doppler radar data revealed the existence of a mesocyclone, mesoanticyclone, microburst, and three-body scatter signature. The cloud top reached up to 17 km, and the maximum radar reflectivity factor was 69-71 dBZ. Analysis of the available radiosounding data, simulation with a numerical model, and the synoptic patterns are also presented.

Loading...

Loading Preview

Sorry, preview is currently unavailable. You can download the paper by clicking the button above.

References (37)

  1. Amburn, S.A. and Wolf, P.L., 1997: VIL density as a hail indicator. Weather Forecast. 12, 473-478. https://doi.org/10.1175/1520-0434(1997)012<0473:VDAAHI>2.0.CO;
  2. Blair, S., Deroche, D., Boustead, J., Leighton, J., Barjenbruch, B., and Gargan, W., 2011: A Radar-Based Assessment of the Detectability of Giant Hail, E-J. Severe Storms Meteorol. 6, 7, 1-30.
  3. Bocheva, L., Simeonov, P., and Marinova T., 2013: Variations of thunderstorm activity in non- mountainous regions of Bulgaria (1961 -2010). BJMH 18, 38-47.
  4. Bocheva L. and Simeonov P., 2015: Spatio-temporal variability of hailstorms for Bulgaria during the period 1961-2010. 15th International Multidisciplinary Scientific GeoConference SGEM 2015, ISBN 978-619-7105-38-4 / ISSN 1314-2704, June 18-24, 2015, Book4, 1065-1072.
  5. Browning, K.A., 1977: The structure and mechanics of hailstorms, Hail: A Review of Hail Science and Hail Suppression. Meteorol. Monogr., No 38, Amer. Meteorol., Soc., 1-43.
  6. Bunkers, M.J., 2002: Vertical wind shear associated with left-moving supercells. Weather Forecast 17, 845-855. https://doi.org/10.1175/1520-0434(2002)017<0845:VWSAWL>2.0.CO;
  7. Carbunaru, D.V., Burcea S., Sasu, M., Antonescu B., and Bell, A., 2010: Three Body Scatter Signature climatology in Romania. ERAD 2010 -The sixth European conference on radar in meteorology and hydrology.
  8. Davies-Jones, R., Burgess, D., and Foste,r M., 1990: Test Of Helicity As A Tornado Forecast Parameter. Preprints, 16th Conf. on Severe Local Storms, Kananaskis Park, Alberta, Canada, Amer. Meteor. Soc., 588-592.
  9. Dimitrova, Ts., Mitzeva, R., Pisarova, Y., Betz, H.D., and Peneva, E., 2013: Relationship between lightning characteristics and radar estimated parameters during pre-severe and severe stages of hail producing thunderstorms developed over Bulgaria. 7th European Conference on Severe Storms (ECSS2013), 3-7 June, Helsinki, Finland.
  10. Doswell, C.A. III and Burgess, D.W., 1993: Tornadoes and tornadic storms: A review of conceptual models. In (Eds. Church et al.) The Tornado: Its Structure, Dynamics, Prediction, and Hazards Amer. Geophys. Union, Geophys. Monogr. 79, 161-172.
  11. Dudhia, J., 1989: Numerical study of convection observed during the Winter Monsoon Experiment using a mesoscale two-dimensional model. J. Atmos. Sci. 46, 3077-3107. https://doi.org/10.1175/1520-0469(1989)046<3077:NSOCOD>2.0.CO;
  12. Edwards, R. and Thompson, R., 1998: Nationwide Comparisons of Hail Size with WSR-88D Vertically Integrated Liquid Water and Derived Thermodynamic Sounding Data, Weather Forecast. 13, 277-285. https://doi.org/10.1175/1520-0434(1998)013<0277:NCOHSW>2.0.CO;
  13. Gospodinov, I., Dimitrova, Ts., Bocheva, L., Simeonov, P., and Dimitrov, R., 2015: Derecho-like event in Bulgaria on 20 July 2011. Atmos. Res. 158, 254-273. https://doi.org/10.1016/j.atmosres.2014.05.009
  14. Grasso, L.D. and Hilgendorf, E.R., 2001: Observations of a severe left moving thunderstorm. Weather Forecast. 16, 500-511. https://doi.org/10.1175/1520-0434(2001)016<0500:OOASLM>2.0.CO;
  15. Hart, J.A., and Korotky, W. 1991: The SHARP workstation v1.50 users guide. National Weather Service, NOAA, U.S. Department of Commerce.
  16. Holleman, I., 2008. Wind observations with Doppler weather radar. TECO-2008 -WMO Technical Conference on Meteorological and Environmental Instruments and Methods of Observation, St. Petersburg, Russian Federation, 27-29 November 2008. http://www.wmo.int/pages/prog/www/IMOP/publications/IOM-96\_TECO- 2008/P1(28)_Holleman_Netherlands.pdf
  17. House, R.A, Schmid, W., Fovell, R.G., and Schiesser, H., 1993: Hailstorms in Switzerland: Left Movers, Right Movers, and False Hooks, Month. Weather Rev. 121, 3345-3370. https://doi.org/10.1175/1520-0493(1993)121<3345:HISLMR>2.0.CO;
  18. Kain, J.S., 2004: The Kain-Fritsch convective parameterization: An update. J. Appl. Meteor., 43, 170- 181. https://doi.org/10.1175/1520-0450(2004)043<0170:TKCPAU>2.0.CO;
  19. Kalnay, E., Kanamitsu, M., Kistler, R., Collins, W., Deaven, D., Gandin, L., Iredell, M., Saha, S., White, G., Woollen, J., Zhu, Y., Chelliah, M., Ebisuzaki, W., Higgins, W., Janowiak, J., Mo K.C., Ropelewski, C., Wang, J., Leetmaa, A., Reynolds, R., Jenne, R., and Joseph, D., 1996: The NCEP/NCAR Reanalysis 40-year Project. Bull. Amer. Meteor. Sosc 77, 437-471. https://doi.org/10.1175/1520-0477(1996)077<0437:TNYRP>2.0.CO;
  20. Klemp, J. and Wilhelmson, R., 1978: Simulations of right-and left-moving storms produced through storm splitting. J. Atmos. Sci. 35, 1097-1110. https://doi.org/10.1175/1520-0469(1978)035<1097:SORALM>2.0.CO;
  21. Lemon L., 1998: The Radar ''Three-Body Scatter Spike'': An Operational Large-Hail Signature, Weather Forecast. 13, 327-340. https://doi.org/10.1175/1520-0434(1998)013<0327:TRTBSS>2.0.CO;
  22. Lindsey, D.T., and Bunkers, M.J., 2005: Observations of a severe, left-moving supercell on 4 May 2003. Month. Weather Rev. 20, 15-22. https://doi.org/10.1175/WAF-830.1
  23. Lim, K.-S.S. and Hong, S.-Y., 2010: Development of an effective double-moment cloud microphysics scheme with prognostic cloud condensation nuclei (CCN) for weather and climate models. Month. Weather. Rev. 138, 1587-1612. https://doi.org/10.1175/2009MWR2968.1
  24. Manros K., Ortega К., and Pietrycha А., 2010: Examining radar 'sidelobe spikes' for severe hail identification. https://ams.confex.com/ams/pdfpapers/175930.pdf
  25. Mlawer, Eli. J., Steven. J. Taubman, Patrick. D. Brown, M.J. Iacono, and S. A. Clough, 1997: Radiative transfer for inhomogeneous atmospheres: RRTM, a validated correlated-k model for the longwave. J. Geophys. Res. 102, 16663-16682. https://doi.org/10.1029/97JD00237
  26. NCEP, 2014: User's Guide for the ARW WRF Modeling System Version 3.5 http://www2.mmm.ucar.edu/wrf/users/docs/user\_guide\_V3.5/ARWUsersGuideV3.pdf
  27. Nielsen-Gammon, J. and Read, W., 1995: Detection and Interpretation of Left-Moving Severe Thunderstorms Using the WSR-88D: A Case Study, Weather Forecast. 10, 127-140. https://doi.org/10.1175/1520-0434(1995)010<0127:DAIOLM>2.0.CO;
  28. Penchev R., Peneva E, 2013: Numerical simulation of extreme convective events during 2012 in Bulgaria using the weather forecast model WRF, Proceedings of the 2nd National Congress in Physical Sciences, 25-29 September 2013, Sofia (in Bulgarian) http://optics.phys.uni-sofia.bg/disk\_CONGRESS/html/pdf/S0751.pdf
  29. Rasmussen, E.N., 2003: Refined supercell and tornado forecast parameters. Weather Forecast. 18, 530-535. https://doi.org/10.1175/1520-0434(2003)18<530:RSATFP>2.0.CO;
  30. Rasmussen, E.N., and Blanchard, D.O., 1998: A Baseline Climatology Of Sounding-Derived Supercell And Tornado Forecast Parameters. Weather Forecast. 13, 1148-1164. https://doi.org/10.1175/1520-0434(1998)013<1148:ABCOSD>2.0.CO;
  31. Simeonov P., Bocheva L., and Gospodinov I., 2013: On space-time distribution of tornado events in Bulgaria (1956-2010) with brief analyses of two cases. Atmos.Res. 123, 61-70. https://doi.org/10.1016/j.atmosres.2012.07.003
  32. Viktor E., Reese S., and Zimmerli P., 2015: Hail losses under the microscope -Comparing losses from three major hail events of the recent past. 8th European Conference on Severe Storms, 14-18 September 2015, Wiener Neustadt, Austria http://meetingorganizer.copernicus.org/ECSS2015/ECSS2015-19.pdf
  33. Weisman, M.L. and Klemp, J.B., 1982: The dependence of numerically simulated convective storms on vertical wind shear and buoyancy. Mon. Weather Rev. 110, 504-520. https://doi.org/10.1175/1520-0493(1982)110<0504:TDONSC>2.0.CO;
  34. Weisman, M. L, and Klemp, J.B., 1984: The structure and classification of numerically simulated convective storms in directionally varying wind shears. Mon. Weather Rev. 112, 2479-2498. https://doi.org/10.1175/1520-0493(1984)112<2479:TSACON>2.0.CO;
  35. Weisman, M.L. and Klemp, J.B., 1986: Characteristics of isolated convective storms. In (Ed. P.S. Ray) Mesoscale Meteorology and Forecasting. Amer. Meteor. Soc., 331-358 https://doi.org/10.1007/978-1-935704-20-1\_15
  36. Zamfirov I., Georgiev Ch.G., and Stotanova, J., 2014: Case study of two splitting hailstorms over Bulgaria on 20 May 2013. ERAD 2014 -The Eight European Conference on Radar in Meteorology and Hydrology. http://www.pa.op.dlr.de/erad2014/programme/ExtendedAbstracts/053\_Zamfirov.pdf
  37. Zrnić, D., 1987: Three-body scattering produces precipitation signature of special diagnostic value. Radio Sci. 22, 76-86. http://ready.arl.noaa.gov/READYamet.php