A significant pattern change is on the way for Houston, with the possibility of showers and thunderstorms by the weekend, with some areas potentially receiving heavier rainfall. The shift begins when winds turn southeasterly and bring warmer, more humid air off the Gulf of Mexico. Friday is expected to be the most likely rain day, with a 40% chance of rain in the forecast. Some areas, particularly southwest of Houston, could see heavier accumulations. The weekend remains uncertain, but forecasters are keeping a close eye on the potential of more widespread showers, particularly on Saturday. If you have outdoor plans, be prepared for a backup plan, especially for Saturday.