Final answer:
The change in weather allows Doris and the dog to continue their relationship outdoors and gives Doris the opportunity to decide if she will keep the dog.
Step-by-step explanation:
The change in weather in the excerpt from 'Stray' moves the plot forward by allowing Doris and the dog to continue their relationship outdoors. With the sun shining and the roads plowed, they have the opportunity to spend time together and strengthen their bond. This change in weather also provides Doris the chance to decide if she will keep the dog.
Learn more about The impact of weather on the plot of a story