NOAA’s Climate Prediction Center (CPC) updated their November forecast on Tuesday and a few changes were made from the forecast issued earlier in the month, along with several similarities. Most noticeable was the addition of cooler than normal temperatures from the Upper Midwest into the Northwest. The previous forecast did not have any below average temperatures in the nation. The warmer than normal forecast in the South was expanded, extending from the Four Corners through the Southeast into the Northeast.
Wetter than normal weather is still expected in the High Plains and Northern Rockies with areas added in the Southwest, Ohio Valley and Great Lakes. Below average precipitation is still expected in the South and Southeast.
— NWSCPC (@NWSCPC) October 31, 2017
— NWSCPC (@NWSCPC) October 19, 2017
The updates and changes listed above were made based on current weather patterns at this time. An active Jet Stream across the northern tier of the nation accounts for the cooler and wetter forecast throughout the North. A ridge in the south is the reason for the warmer and drier forecast in most of the South.
The CPC mentions that significant variability exists in some of the tools used for the forecast for this month. Uncertainties exist with the strength and timing of the upcoming La Nina, along with fluctuations in the Jet Stream pattern, which can shift quickly during this time of the year.
For WeatherNation: Meteorologist Mace Michaels