NOAA winter outlook: wetter South, drier north, warmer nearly everywhere as El Niño strengthens

Mixed · 2NOAA released its winter outlook for December to February on Thursday 15 October, forecasting wetter-than-usual conditions in a southern band of the US, including parts of states that have had long-standing drought. 1 2 Mixed · 2Forecasters attribute the pattern largely to a strong El Niño, a natural warming of the tropical Pacific that shifts weather worldwide; AP reports that forecasters globally expect it to reach record levels this fall or winter. 1 2 Mixed · 2According to CBS News, the outlook has the Southwest, Southeast and parts of the East Coast likely wetter than average, while parts of the Great Lakes, the northern Mountain West, Hawaii and much of Alaska may be drier. AP says parts or all of 39 states are forecast to be wetter than usual, with much of Montana and parts of Oregon, Idaho, Wisconsin and Michigan drier. 1 2

Mixed · 2On temperature, AP reports that part or all of 41 of the Lower 48 states are forecast to be warmer than normal and none cooler than average. CBS lists warmer-than-average areas including northern California, the Pacific Northwest, the Midwest, the Mississippi Valley, much of the eastern US and Alaska, with near-normal temperatures expected across much of the lower half of the country, including Florida. 2 1 Mixed · 2NOAA expects drought to ease across large areas. Meteorologist Jon Gottschalck said drought should improve or end in western Oregon and western Washington, the Southwest, the central and southern Rockies, the southern Great Plains, the lower Mississippi Valley and areas in the East. CBS adds that drought could develop or worsen elsewhere, including eastern Washington, parts of Oregon and the northern Rockies. 2 1 Centre · 1AP notes that wetter does not mean snowier: the weather service does not make seasonal snowfall predictions, but its meteorologists said much of the north, including the Northeast, Great Lakes, Upper Midwest and Northern Rockies, should expect below-normal snow, while the Southern Rockies and parts of the Southeast and Southwest may get more. AccuWeather forecasts half or less of normal snow for Chicago, Boston, New York and Philadelphia. 2

Mixed · 2National Weather Service Director Ken Graham said a strong El Niño does not reduce winter weather risks, and warned that too much precipitation on dry soil can fuel destructive flash floods and mudslides. The Weather Channel's Mike Bettes said California could see numerous high-impact atmospheric rivers bringing flooding and landslides, and Gottschalck said Florida and the Southeast should watch for more tornadoes. 1 2 Centre · 1AP also reports that the polar vortex should occur less than in most winters, though not necessarily not at all, and that MIT researcher Judah Cohen said an unprecedented El Niño is a reason to be less confident, since there is no historical analog. 2 Centre · 1AP adds that US winters have warmed about 4 degrees in the past 50 years, predominantly from human-caused climate change, according to NOAA. 2