A look at the oceans shows that the Pacific has cooled considerably in 2017, and we have technically entered a La Niña episode. All of that "blue and green" off the West Coast of South America is indicative of cooler than average water and represents a developing La Niña.
It looks like a weak La Niña episode is going to be an influence for this upcoming winter, and possibly last into spring. The graphic below shows several models and their ENSO forecast. The yellow line is the mean of all of the models...
The models keep us in a weak La Niña through late winter, before weakening the signal as we head into spring.
What weather pattern usually influences the United States during a La Niña? Check out the map below.
Let's look at the latest models and what they have to say for the next three months.
NMME Model Forecast
The NMME Model would suggest average precipitation, with above average temperatures for Southeast Colorado.
CFS Model Forecast
The CFS Model shows average precipitation with above average temperatures.
The JAMSTEC Model shows average to slightly above average precipitation, with average to slightly below average temperatures.
The maps below show what Colorado can usually expect during a La Niña episode.
The map shows above average temperatures for more of Southeast Colorado, with the exception of two places: 1) The Wet and Sangre de Cristo Mountains are historically colder than average 2) Areas north of HWY 50 closer to I-70...
Historically, La Niña means below average precipitation for most of Southeast Colorado. This is especially true for the Southeast Plains...
As of right now, we don't have a solid reason to argue with what history is showing for Southeast Colorado. While there will be frequent temperature changes, and wild swings regarding temperature, Southeast Colorado will likely see average to above average temperatures. We are also forecasting below average precipitation. La Niña episodes can also make for some pretty windy times. Strong chinook wind events are more prevalent during La Niña episodes. Aside from the chinook wind events, we are usually also quite windy from the frequent cold fronts that move through.
Below is our temperature and precipitation winter (Dec, Jan, Feb) outlooks: