early on may 4, an area of low pressure formed about 140 km (85 mi) to the west of palau island. on that same day, the low pressure starts to strengthen rapidly with improved llcc, tightly–wrapped shallow convective banding and a well–defined center. on the next day the low pressure starts to move northwest in general direction to the seas east of philippine islands. however it remained almost stationary by afternoon due to the influence of high pressure in the northeast of the system. by that time, its llcc starts to become elongated and the system was also in favorable sea surface temperatures with low vertical wind shear. later of that day, its llcc starts to consolidate again and the system starts to move northwest slowly, whilst the japan meteorological agency upgraded the system into a tropical depression in the afternoon of may 6, joint typhoon warning center upgraded the low pressure into a tropical depression. in the same evening, pagasa upgraded the low pressure into a tropical depression and assigned its local name 'bebeng'. in the afternoon of may 7, jma upgraded the tropical depression to a tropical storm, and assigned the name 'aere'. during the early morning of may 12, the jma downgraded aere to a tropical depression while south of kyushu island.