Will the strongest El Niño in almost 20 years mean relief for drought-stricken California? Should New England brace for another snowy winter? NOAA’s Winter Outlook, issued on October 15th, offers a look at what’s most likely to occur. After flirting with El Niño last winter, the atmosphere finally began responding to the warming ocean last spring. Since then, sea surface temperature departures have steadily increased. And heading into winter, we are seeing values not seen since the big 1997/98 episode. Strong El Niños are known to exert a significant influence on our weather and climate, particularly during winter, so not surprisingly, the outlooks this year reflect El Niño impacts. Above-average temperatures are favored across much of the West and the northern half of the contiguous United States. Temperatures are also favored to be above average in Alaska and much of Hawaii. Below-average temperatures are most likely in the southern Plains and in the Southeast.
Remember, these maps show only the most likely outcome. There is always some chance that seasonal temperature will be below, near, or above average. Both temperature and precipitation predictions have parts of the country labeled “EC” for “equal chances”, which means there is no tilt in the odds towards either above-, near-, or below-average temperature or precipitation. An enhanced storm track favors above-average precipitation along the southern tier of the nation from California, through Texas to Florida, and along the East Coast to New England with wetter-than-average conditions also favored in southern Alaska. Below-average precipitation is most likely in Hawaii, central and western Alaska, in parts of the Pacific Northwest and northern Rockies, and around the Great Lakes and Ohio Valley. While the precipitation outlook suggests good news for California, one season of above-average rain and snow is unlikely to erase four years of drought.
The Drought Outlook shows some improvement is likely in central and southern California by the end of January, but not drought removal. Additional statewide relief is possible during February and March. Drought removal is likely across large parts of the Southwest, while improvement or removal is also likely in the southern Plains. However, drought is likely to persist in the Pacific Northwest and northern Rockies, with drought development likely in Hawaii, parts of the northern Plains and in the northern Great Lakes region. So what about snow? Remember, the Winter Outlook focuses on climate conditions. It doesn’t address typical winter hazards, such as extreme cold or snowstorms, which result from rapidly evolving atmospheric conditions and which can happen even during a mild winter.
Stay tuned to NOAA to be weather-ready and climate-smart. From NOAA’s Climate Prediction Center, I’m Mike Halpert..