Threat of thunderstorms rises with humidity

After several days of sunshine and comfortable temperatures, clouds and light showers arrived late Saturday, signaling the approach of our next weather system.
Winds are to turn southerly by Sunday, bringing an increase in humidity. As moisture levels rise, the air will become unstable, resulting in scattered thunderstorm development in the afternoon and evening. Cool air in the mid- and upper levels of the atmosphere will keep our weather unsettled through Monday, with scattered thunderstorms likely.
Meanwhile, Harvey is expected to weaken to a tropical depression as it lingers along the Texas Gulf Coast. Catastrophic flooding may persist as it inches its way northeast. In July 1979, tropical storm Claudette swamped Alvin, Texas, with 42 inches of rain in one day.