Episode 158
Ash and friends finally arrive in Fuchsia City with the Battle Pike only a day away. May's egg then begins to glow signaling that it is ready to hatch. However, before she can celebrate her Squirtle runs off. May finds Squirtle at the train station with an old lady named Edna. Meanwhile, Team Rocket decides to divide and conquer to capture everyone's Pokémon. Back at the train station, Edna explains that she is waiting for her husband to return. Then Edna's granddaughter, Katrina, shows up and gets her Grandma to go home. Katrina tells May that many years ago Edna's husband, Jonathan, left for the big city in order to become a Pokemon Doctor. Edna tried to reach the station but the train left before she got there and she wishes it had just been snowing that day so she could have told Jonathan they were going to have a baby. One year later, he died in an accident but she refuses to believe it. She also tells May that Edna lost her pendant that day. When May and Squritle find the pendant, they, along with Meowth (who was following and listening to them), get transported back in time to that exact day, and decide to fix Edna's future by fixing the past by making sure that it starts to snow.
Aired 22/12/2005EP 158 - Episode 158

Pokémon the Series: Ruby and Sapphire
After participating in the Johto League, Ash decides to begin anew in yet another journey; this time by himself and Pikachu, in the land of Hoenn. Though he isn't alone for long, as 10-year-old May (who dislikes Pokemon, but just wants to come along to see the world) travels with him after Pikachu destroys her bicycle. Ash also meets up with his old companion, Brock, and May's younger brother, Max. Together, they travel along in Hoenn, battling Gym Leaders, entering Contests, and other events on the way to the Hoenn League.
(Source: Anime News Network)