How were the writer and his friends affected by the weather forecast

Harris and J. are greatly irritated with George, and their mood grows worse when they learn that the day’s weather forecast is poor. J. digresses to complain about how often weather forecasts are inaccurate. He also concocts a hypothetical story about staying inside when the forecasts predict rain and missing a beautiful day, and then believing the forecast of sun the next day, but ending up wet.