In a state where dead trees in the Sierra Nevada still stand as a testament to a severe seven-year stretch of dry weather that ended in 2017, some nervously wonder whether the state may slide back into a drought. In the eastern Pacific Ocean near the equator, ocean temperatures are pretty stable. That means there’s no El Niño or La Niña sitting out there to help drive a chain of storms to dump rainfall on the Valley and snow in the Sierra Nevada as the calendar closes on 2018.