It may be spring, but it's not too soon to look ahead to summer weather, especially when El Nio " a player in last year's especially brutal summer " is rapidly weakening and will all but vanish by the time the season kicks into gear. The influence of El Nio or La Nia on US weather isn't as clear-cut in the summer as it is in the winter, especially during a transition between the two phases, said Michelle L'Heureux, a climate scientist with the Climate Prediction Center.