MCKINNEY, Texas -- It was supposed to be a dream family vacation in Cabo San Lucas, Mexico. But twin sisters, Barbara Thomas and Beverly Sckripsky, 67, were swept away by a killer wave.

Their families are at a loss.

"You had two wonderful people just walking on the beach and full of life a couple hours before that, and they're now gone," Steve Thomas, Barbara's husband, said.

The two lived in McKinney. They started dating in middle school and had been married for 45 years. Thomas remembers his wife as a kind, magnetic woman who loved helping others.

"Anybody that knew her, loved her," said Thomas.

Oct. 22 was the third day of what should have been a week-long vacation. Thomas remembers the last time he saw his wife alive.

"My last memory was, 'Come with us and go on the walk,'" said Thomas. "And I didn't go. I literally watched her walk out the door and she wanted me to go with her."

Barbara and Beverly were walking on the beach when a large, powerful wave pulled them into the ocean, and they drowned. When they didn't return, Thomas and his family alerted authorities and went looking for them.

"We found one of their sandals and when we found the sandal it was like.... My head told me they were gone, but my heart hoped against hope," Thomas said.

The so-called "rogue waves" have killed multiple tourists in that area, prompting the U.S. Embassy in Mexico to issue a warning about potentially deadly conditions on beaches in areas that aren't always clearly marked.

"Beaches on both the Pacific and Sea of Cortes sides of the Baja California peninsula, near Cabo San Lucas and San Jose del Cabo, can be dangerous due to strong currents, riptides and rogue waves," said the warning, in part. "Swimmers, waders and even people simply walking along the beaches have been washed into the ocean by rogue waves. Some have drowned and others have disappeared. Surfers and other water sports enthusiasts should always inquire about local conditions before going into the water."

Thomas experienced it first hand.

"[The wave] went up five feet every second, from five feet to 20 feet, and I was literally just looking at a wall of water," he said.

The twins were best friends who loved traveling together and planning family trips. At 67 years old, they were full of love and life.

Now Thomas hopes their story will help save someone else.

"There are certain beaches there that are killer beaches," said Thomas. "If you're out on the beach or in the ocean, you need to be very, very cautious of what's going on around you."

Friends and family will hold a joint Celebration of Life service Nov. 18 at Christ United Methodist Church in Plano.