Various oceanographic phenomena are associated with characteristic causative processes and seasonal timing: rip currents are narrow, seaward-flowing jets formed by the convergence of longshore currents in the nearshore zone, oriented roughly along-shore in their formation dynamics; thermal inversions in the upper ocean (such as in the Bay of Bengal) are associated with low-salinity surface water and occur predominantly during the winter season; and the Somali Current is a strong seasonally reversing western boundary current that intensifies dramatically during the summer southwest monsoon.