Lost in the Snow is a 1987 annual story.
It's winter and Thomas is cross because he has to wear his snowplough. Worst of all, his water tanks need to be filled, but when they stop at the junction, the water column is frozen. As they wait for the passengers to board the coaches, a lady gives her cat to her daughter, who will look after him while she goes away for Christmas. But when Thomas stops at Dryaw, the cat jumps out of the basket and runs away. The passengers search for the cat while the crew fills Thomas' water tanks with snow because the water column there is frozen too. However, time is running out to find the cat. But as Thomas' crew finishes filling his water tanks, they find the cat hidden in a heap of snow. Soon after, the cat is dry and warm and his owner places him safely back in the basket and the train leaves on its way.