San Diego lifeguards hope a high tide Wednesday morning helps float a dead 50-ton fin whale off the coastline near Sunset Cliffs so it can be towed away for disposal at the city landfill.The 50-foot-long female whale was spotted Saturday morning in a secluded part of the coast unreachable by the public.The plan is to hook the whale to the back of the lifeguard service's 35-foot boat to be towed to Fiesta Island in Mission Bay.Once at Fiesta Island, the carcass will be inspected by experts from the National Marine Fisheries Service in La Jolla before being taken by truck to the Miramar landfill."There is definitely a science opportunity here," said Lifeguard Lt. Greg Buchanan.The high tide is set for 6:50 a.m. Weather predictions are for calm seas and light winds, which would be helpful, Buchanan said."It's all about Mother Nature," Buchanan said.The cause of the whale's death is undetermined. Near the carcass is a 5-foot-long fetus, which was still alive Tuesday morning but in distress.