If you don’t think California has seen enough rain this year, just wait. There may be more to come. Federal forecasters said Thursday that the chances of an El Niño developing by fall are on the rise — now between 50 and 55 percent —an outlook that could skew the odds in favor of yet another wet winter. “There are a lot of players on the (weather) field,” said Emily Becker, a research scientist with the Climate Prediction Center, the federal agency that released the latest report on the El Niño climate pattern.