Sounding-derived parameters associated with tornado occurrence in Poland and Universal Tornadic Index

The environment associated with significant tornadoes in Bangladesh

“…This is likely due to high SST in the Bay of Bengal and the relatively high equilibrium levels due to high tropopause heights at the low latitude of Bangladesh (~25°N). The LCL height and mid-level lapse rate were found to be comparable to studies over the U.S. Deeplayer shear that was found to be slightly less than the previous studies over the U.S.; however, low-level (0-1 km AGL) shear was found to be considerably less compared with studies over the U.S. (Thompson et al, 2003;Cohen, 2010) and Europe (Taszarek and Kolendowicz, 2013). It is hypothesized that many events would be characterized by high CAPE and sufficient deep layer shear for supercells that exhibit discrete propagation along a low-level convergence boundary.…”

“…Deep-layer shear values were slightly less than those found in studies over the U.S. (e.g., Thompson et al, 2003;Rasmussen and Blanchard, 1998;Lane, 2008) and Poland (e.g., Taszarek and Kolendowicz, 2013); however, the low-level shear values were even less. The median 0-1 km shear is 7.5 m s (Fig.…”

“…The median LCL values in the Bangladesh cases (Fig. 12) are slightly higher (1083 versus 1004 m AGL) and span a greater range than the significant tornado category presented in Thompson et al (2003), and higher than 945 m, from Taszarek and Kolendowicz (2013) for F2/F3 tornadoes over Poland. This is most likely due to the inclusion of cool season events Table A1 (Fig.…”

“…Afrose et al (1981) considered tornado and nor'wester events between 1975 and 1979. Utilizing a blend of multiple sources to collect tornado reports has been employed in similar studies of tornadoes over Europe (e.g., Gayá, 2011;Brazdil et al, 2012;Taszarek and Kolendowicz, 2013;Simeonov et al, 2013). In addition, at least one of five criteria was used to determine if the event was tornadic (note Appendix A lists the criteria met with numerous events associated with multiple criteria).…”

Large Hail in Poland in 2012

“…This so called "loaded gun sounding" provides that if warm air has sufficient lifting forcing to overcome inversion, it usually "explodes" in afternoon hours and results in the severe convective thunderstorms. Severe weather threats found with these thunderstorms are: large hail, heavy precipitation, severe wind gusts and sometimes tornadoes (if the wind shear is large enough; Groenemeijer and van Delden 2007, Taszarek and Kolendowicz 2013). These kind of thunderstorms occurred in the warm sector of the synoptic low (in front of the cold front) in south-eastern Poland.…”