when did tropical storm leslie form in 2018
2018 Atlantic hurricane season In the midst of an active September, the NHC began monitoring an area southwest of the Azores for tropical or subtropical development within the next several days on September 19.[126] A non-tropical area of low pressure formed on September 22,[127] quickly transitioning into a subtropical storm by 15:00 UTC on the next day, with the NHC assigning the storm the name Leslie.[128] After little change in strength had occurred in two days, Leslie began to weaken, first into a subtropical depression early on September 25,[129] before becoming post-tropical later that day as the system began to merge with an approaching frontal system.[130] Leslie subsequently merged with the frontal system and began a cyclonic loop to the west, intensifying during this time, and becoming a powerful extratropical cyclone with hurricane-force winds early on September 27.[131]