Those predawn sprinkles on Thursday, Nov. 13, were perhaps a sign of things to come. Though only a trace ended up in local rain gauges, the air quality, which has been in the UNHEALTHY range since Friday, Nov. 7, was drastically improved. Next chance for precipitation is Sunday. The unstable pattern will continue through the week. Highest probability of significant rainfall similar to what was recorded on Halloween night is a week from Saturday when forecasters are predicting a 40 percent chance.