Abstract
The Brazilian state of Alagoas is occasionally affected by thunderstorms. Aiming to mitigate these disorders, the present study suggests a better understanding of synoptic systems associated with thunderstorms. DECEA and TRMM satellite data were used to estimate the frequency of thunderstorms. Reanalysis data from NCEP have been also used. Thereby, 212 thunderstorm events were found during 15 years. The highest thunderstorm frequency (21 events) was observed in 2008 and the smallest frequency was observed in 2012 (04 events). January, February and March are the months with the highest thunderstorms number. Five synoptic systems associated with thunderstorms have been identified: Trough at the Upper Levels (TUL), Intertropical Convergence Zone (ITCZ), Upper Tropospheric Cyclone Vortex (UTCV), Frontal Zone (FZ) and Middle Tropospheric Cyclone Vortex (MTCV). UTCV and TUL were detected as the systems with the highest thunderstorms number. The Instability Indexes showed strong instability for the UTCV, ITCZ and TUL, and low instability for the MTCV.
Keywords:
Thunderstorm; synoptic systems; instability index
