Complex sentence: By the afternoon of August 30, banding features became evident and the system became more circular and convective in nature, and the depression was upgraded into Tropical Storm Hernan with sustained winds of 45 mph (72 km/h).
Split into simpler sentences: By the afternoon of August 30, banding features became evident and the system became more circular and convective in nature. Thus, the depression was upgraded into Tropical Storm Hernan with sustained winds of 45 mph (72 km/h).