Last week, NOAA’s Climate Prediction Center (CPC) issued their December outlook. Above average temperatures and precipitation are expected across much of the West. The Southeast will likely see wetter than normal weather. From the Northeast into the middle South, a drier than normal month is in the forecast. Colder than average weather is expected for the Great Lakes.
Our initial monthly forecast for December anticipates increased odds for above-normal precipitation extended from California through the Northern Plains, the Southeast through Mid-Atlantic, and across much of Alaska. https://t.co/ZojpnS5Ja5 pic.twitter.com/9X4UxTvaSt
— NWSCPC (@NWSCPC) November 15, 2018
The outlook was based primarily on model forecasts and long term trends. The influence of tropical thunderstorms near the Equator (Madden-Julian Oscillation) and Arctic cold air (Arctic Oscillation) were also considered.
Given the current atmospheric state, the onset of El Nino played a minor role in the forecast according to the CPC. This differs from the winter outlook, which was updated last week. Even with El Nino already showing signs of development, it’s effects on the atmosphere are not expected to be observed until later in the winter.
For WeatherNation: Meteorologist Mace Michaels