A coastal flood advisory is issued by the National Weather Service of the United States when coastal flooding along the coast of the Atlantic Ocean, Pacific Ocean, or the Gulf of Mexico is occurring or imminent, but does not pose a serious threat to lives or property, but rather will simply pose a nuisance to people in the affected area. The flooding must be due to water being forced from the nearby body of water onto land, and not from rainfall. Nor'easters, hurricanes, tropical storms, and thunderstorms can all lead to the issuance of a coastal flood advisory.