Its transformation to a tropical system occurred over water cooler than 24 ° C ( 75 ° F ) , much colder than the 26.5 ° C ( 80 ° F ) usually required for tropical development .
It became a tropical storm the next day in water cooler than 24 ° C ( 75 ° F ) , colder than the 26.5 ° C ( 80 ° F ) usually needed for tropical storms .