On Monday morning, September 9, Hurricane Dorian was a post-tropical storm after a mid-latitude weather front and cold seas had altered its tropical characteristics over the weekend. On Saturday and Sunday, Hurricane Dorian struck eastern Canada, causing wind damage and bringing heavy rainfall. According to the Associated Press, a peak of 400,000 people were without power in Nova Scotia, Canada, because of Dorian.
Hurricane Irma dropped extremely heavy rain at times during it’s trek from near the Cape Verdi Islands through the northern Leeward islands, Cuba and the southeastern United States. Over 16 inches (406 mm) of rain was reported in Guantanamo, in the easternmost province of Cuba, as the category five hurricane battered the country. Almost 16 inches (406 mm) of rain was also reported at Fort Pierce on the eastern side of Florida. Charleston, South Carolina reported 6 inches (152.4 mm) of rain in 24 hour.
Tropical storm Cindy was downgraded to a tropical depression after moving onshore near the Texas and Louisiana Border on Thursday June 22, 2017. Flooding was reported along the the Gulf Coast even before Cindy made landfall. The rainfall around tropical storm Cindy was asymmetrical. The majority of heavy rainfall with the tropical cyclone was located east of Cindy's center in the states along the Gulf Coast from Louisiana through the Florida Panhandle. The tropical depression continued to spread heavy rain and occasionally severe thunderstorms after it came ashore.
Hurricane Matthew devastated western Haiti and killed over 1,000 people. Matthew also took the lives of at least 37 deaths in the United States with 18 deaths occurring in the state of North Carolina. Flooding is still widespread in North Carolina. Some rivers in North Carolina such as the Tar and the Neuse are still rising.
In order for Hermine or any other tropical depression, to intensify there must be a pathway for heat energy from the ocean surface to enter the atmosphere. For Hermine, the conduit may have been one of the two "hot towers" that the Global Precipitation Measurement mission or GPM core satellite observed on Aug. 31 at 4:09 p.m. EDT (2009 UTC).