Long-Term Meteorological Characteristics and Extreme Climate Indices over Tirupati - A Rapidly Developing Tropical City

Tirupati's climate has witnessed notable precipitation and temperature pattern shifts. The annual precipitation displays marked interannual variability over the past decades, notably marked by a substantial increase during the southwest monsoon (JJAS). However, a concerning long-term trend emerges, indicating a decrease in total annual precipitation over the last 30 years. The city has experienced contrasting trends in wet and dry days, with a significant long-term increase in wet days during both the southwest (JJAS) and northeast (OND) monsoons, yet a recent decrease over the past three decades. Concurrently, a noteworthy rise in the annual dry days has been observed during the same period. Heavy precipitation events, particularly during the southwest monsoon, show a positive trend, contrasting with the absence of significant changes in heavy rainfall days during the northeast monsoon. Temperature trends reveal a warming scenario, with a significant positive trend in annual maximum temperatures (T max ) and a consistent annual rise in mean minimum temperatures (T min ). However, the mean T max during the summer and southwest monsoon months shows no significant changes. A substantial decrease in cold and very cold days, especially during the last 30 years, suggests a broader warming trend impacting seasonal temperature variations in Tirupati. The findings underscore the complex interplay of monsoons, temperature variations, and changing precipitation patterns in Tirupati's climate over the years. This information is essential for planning, managing, and mitigating the city's weather extremes, planning and resources management and infrastructure projects.