Wettest and driest hours of day during the southwest monsoon season over Indian region

Abstract

The spatial distributions of wettest and driest periods of the day during the SW monsoon season over Indian region are presented in the form of charts. The hourly rainfall values for 40 self-recording raingauge stations with data period of 5-9 SV monsoon seasons have been used for this purpose. The chart for maximum rainfall activity showed that the wettest period occurs in the afternoon hours over the main land region and in the night hours over the coastal region. This difference in time of maximum I considered to be the effect of the differential response of the solar influence on precipitation formation mechanism over continental and coastal areas. The chart for minimum rainfall activity indicated that the driest period occurs in the forenoon hours of the day over a large portion of Indian region and there is no significant difference in the occurrence hours of the driest period over the main land region and the coastal region of India. Results of some of the earlier relevant studies are briefly discussed.