CLIMATE PREDICTIONS—KIND OF like romantic comedies—are full of will they/won’t they suspense. Like this year’s La Niña. In September, the National Weather Service cancelled its months-long lookout for the climate phenomenon—which, as a counterpoint to El Niño, is associated with cooler overall global temperatures. Then, last week, the agency reversed. Its Climate Prediction Center predicted a 70 percent chance of La Niña forming, and folded that prediction into its Winter Weather Outlook. If true, that means the next few months will be warm and dry in the southern half of the US; wet and cool in the north.