Climatic Drivers influencing the formation of AR
The initiation of the monsoon season in the Indian South Continent occurs in May, peaking in the region during the month of June. In order to distinguish between the monsoon onset and the formation of Atmospheric River, we evaluated the impact of the Low-Level Jet (LLJ) on the development of AR. Figure 3 displays the Wind Speed and Geopotential Height at a 500 hPa level for the time period of 15 June 12 AM in both 2021 and 2022. During the onset of the monsoon season, there is a movement of strong winds from the Indian Ocean into the Bay of Bengal in mid-June. This movement results in the provision of moisture in India and Bangladesh, as illustrated in Figure 3 (a) for the year 2021, when the AR was not formed. In contrast, Figure 3 (b) depicts the observation of a prominent high-velocity wind jet in 2022, which traverses the Northern area of India and extends towards the Pacific Ocean, encompassing Bangladesh and the neighboring nations. This jet facilitates the rapid movement of moisture in a narrow corridor, resulting in the formation of an Atmospheric River on 15 June 2022.