As soon as we hit the right forecast, we'll be off to Havana. We won't know the exact starting point probably until the night before. And we don't know exactly where landfall will be...I'd love to wind up in Key West, but it will depend on trajectory of the Gulf Stream." Nyad estimated that the cost of her "expedition" was about $500,000. Nyad moved her training site from the Caribbean island of St. Maarten to Key West, Florida, in June 2011. She was joined by key members of her support team on June 28, to wait for ideal weather conditions that typically occur only during the summer doldrums in July and August. For the marathon swim to be feasible, two main weather conditions needed to come together at the same time: a combination of low-to-light winds (to minimize sea chop), and water temperatures in the high 80s °F (high 20s/low 30s °C). These relatively "high" water temperatures produce a twin challenge: in the first half of her swim the warm water will dehydrate her body, while in the second half her body temperature will drop and she will face potential hypothermia. Nyad had bulked up her physique to about 150 pounds/70 kg (15 pounds/7 kg more than she weighed in 2010) to help counter the loss of body mass during her grueling swim. Nyad was escorted by a paddler in a kayak equipped with an electronic shark repellent known as a Shark Shield. To keep Nyad swimming in a straight line, her specially designed, slow-moving catamaran support boat deployed a streamer: a long pole keeps the streamer several yards away from the boat, and the streamer is designed to remain about 5 feet underwater, so that Nyad can swim above it, much like following a lane line in a swimming pool. At night, the white streamer was replaced by a string of red LED lights. Writing in her blog in July 2011, Nyad stated that the development of the submerged guide streamer, in early summer 2011, may be the single greatest aid to her marathon swim. In all of her previous swims, she had trouble keeping the support boat in sight and was prone to veer off-course. Keeping a boat headed in a straight line, in the ocean, while moving at only 1 to 2 knots is very difficult, and her catamaran is equipped with thrusters and a special sea anchor (in case of following seas) to stabilize its course.