(CBS/AP) KEY WEST, Florida - Diana Nyad slogged across the Straits of Florida for a third straight day Monday, advancing toward a swimming record on calm seas after enduring a night of stormy weather.
Nyad, who turns 63 on Wednesday, is making her third attempt since last summer to become the first person to swim from Cuba to Florida without a shark cage. She also made a failed try with a cage in 1978.
"She's doing well," a spokeswoman for the swimmer, Alex Crotin, said Monday afternoon.
Watch: Diana Nyad swimming from Cuba in fourth try
Watch: Exercise counselor on Nyad: This is her Mt. Everest
(Watch CBS "This Morning" Correspondent Tammy Leitner report on the progress of Nyad's swim Monday morning.)
Nyad had been expected to arrive somewhere in the Florida Keys early Tuesday, though her team didn't say how much overnight storms Sunday might delay her. Her team tweeted that a storm had blown Nyad off course and that "all hell broke loose" in the squall.
Monday appeared to be offering far more ideal conditions, with blue skies and level seas.
Nyad's team tweeted Monday morning that she was "swimming strong" in calm seas at 50 strokes per minute. She hit the 48-hour mark in the water on Monday afternoon; she estimated it would take at least 60 hours to reach Florida.
Australian Susie Maroney successfully swam the Straits in 1997, but she used a cage. In June, another Australian, Penny Palfrey, made it 79 miles (127 kilometers) toward Florida without a cage before strong currents forced her to abandon the attempt.
Jellyfish stings forced Nyad to cut short her second of two attempts last year as toxins built up in her system. CBS "This Morning" reports that she is wearing a special suit to protect her from jellyfish this time around, but already endured stings on her lips and forehead.
Nyad has been training for three years for the feat. She's accompanied by a support team in boats and a kayak-borne apparatus shadowing Nyad helps keep sharks at bay by generating a faint electric field that is not noticeable to humans. A team of handlers is always on alert to dive in and distract any sharks that make it through.
She takes periodic short breaks to rest, hydrate and eat high-energy foods such as peanut butter.
