VAMA VECHE WATERSPOUTS OF 16 JULY, 2013
C. MARINESCU, V. ARGHIUȘ, L. O. MUNTEAN
ABSTRACT. – Vama Veche waterspouts of 16 july, 2013. As it is known, waterspouts generally occur in unstable thermodynamic stratification, light wind in the low troposphere and high Convective Available Potential Energy (CAPE) in the low layers. High values of CAPE are not necessary if there is heavy windshear in the first 3 km from ground level. Waterspouts can be produced by storm clouds with both supercell and non-supercell structure. The existence of the analyzed waterspout event was checked based on the general conditions for waterspouts and tornadoes occurrence, as proposed by Houze and Dotzek. The possibility that waterspouts occur was also verified using the Szilaghyi nomogram. In this context event, the synoptic, mesoscale environment and radar data highlighted the light wind in the lower troposphere, the occurrence of a low-level “hook” echo and of rotating structures in the radar reflectivity field, the presence of the radar signature of a mesocyclone and the existence of instability, sufficient moisture and wind shears in the lower boundary layer. Moreover, with the help of in-situ pictures, it was proved that the Vama Veche storm cloud did not preserve its mesocyclone stage and produced a series of waterspouts.
Key words: waterspout, Vama Veche, CAPE, mesocyclon, Szilaghyi nomogram