Sunday, 02 December 2007 23:38

La Niña Winter Forecast

National Oceanic and Atmospheric Administration forecasters have forecast a La Niña winter this year. La Niña is characterized by unusually cold ocean temperatures in the Pacific, compared to El Niño events, which are caused by unusually warm ocean temperatures. La Niña tends to bring nearly opposite effects of El Niño to the United States — wetter than normal conditions across the Pacific Northwest and dryer and warmer than normal conditions across much of the southern tier.

Michael Halpert, head of forecast operations and acting deputy director of NOAA’s Climate Prediction Center says, “The big concern this winter may be the persistence of drought across large parts of the already parched South. And while December through February is likely to be another milder-than-average winter for much of the country, people should still expect some bouts of winter weather.” Here in central California, we are right on the dividing line and have a fifty-fifty chance of either extra cool and wet or extra warm and dry winter weather. The last La Niña winter was in 1995. November was an extra dry this year, with rainfall at about 50% of normal. And meteorologists at the State Department of Water Resources say that La Niña years that start out dry generally stay dry, running about 50 – 90% of normal precipitation for the year. Coming off a dry year, that’s a concern to water providers, ranchers, and gardeners alike.