Response of the atmospheric boundary layer to cold pools of thunderstorms at rural location, Gadanki

The thunderstorms produce cold pools that spread horizontally few kms from the location of cumulonimbus clouds. They are often seen during the noon-evening period. The atmosphere and several surface meteorological parameters show a sudden change during the passage of these cold pools. An earlier study has noted that 85% of gust events observed at Gadanki, India are associated with these cold pools (and thunderstorms). Cold Pools are mainly found to occur in the months of April, May and June during 11 years’ time from 2010 -2021 over Gadanki. A total of 84 cases of cold pools were seen during this period with highest number of cold pools occurring in the noon-evening time 3 pm- 4 pm, followed by the time intervals of 2 pm- 3 pm and 4 pm- 5 pm. The atmospheric variables (temperature, wind speed, pressure and humidity) are used to determine the onset of a cold pool using meteorological tower data. It is interesting to note that we have observed cold pools with heavy rainfall and cold pool events with drastic changes in all these parameters but no rainfall. Wind profiler data shall provide a better understanding of these cold pools.