Variability of Lightning and Thunderstorms in Peninsular Malaysia

Thunderstorms and lightning activity depend on location, climate, and time. Understanding these variations aids in comprehending lightning and thunderstorm formation, outdoor activity planning, power reliability, and severe weather occurrences. This study examines the variability in monthly, yearly, and seasonal lightning data from 2011 to 2018, obtained from the Lightning Detection Network System (LDNS) operated by Tenaga Nasional Berhad Research (TNBR) Sendirian Berhad in Peninsular Malaysia. The study showed an optimal 44% total cloud-to-ground (CG) lightning frequency. October experienced the most CG lightning, and February the least. Positive cloud-to-ground (+CG) lightning accounted for 13.2% of annual lightning, while negative cloud-to-ground (-CG) lightning comprised 86.8%. The first Inter-Monsoon (IM1) season had 30% of the annual CG lightning, with 72% resulting from -CG lightning and 28% from +CG lightning. The second inter-monsoon (IM2) season saw about 28% of annual CG lightning, with 94% -CG and 6% +CG. In the Southwest Monsoon (SWM) season, 27% of annual CG lightning was recorded, with 93% -CG and 7% +CG. The Northeast Monsoon (NEM) season exhibited moderate CG lightning activity at 15% of the annual total, with 95% -CG and 5% +CG. Regional thunderstorm days averaged 180 per year, predominantly occurring in October and November. During the eight years, the majority of thunderstorm days (TDs) occurred between the 17th and 21st of each month. Locally, CG lightning was most frequent between 1400 LT and 1600 LT in the afternoon and evening. The hourly trend shows CG lightning increasing from 1000 LT to 2000 LT, peaking at 1600 LT. According to the study, lightning activity is increasing in terms of temporal distribution, seasonal variation, and daily and hourly trends. Thus, improving lightning and thunderstorm protection and forecasting in this region is crucial for safety.