Updated September Forecast From the Climate Prediction Center
Late last week, the Climate Prediction Center updated the September forecast, expanding the area of cooler than normal temperatures. Below average temperatures are now expected from the Mississippi Delta to the Great Lakes. The previous outlook, issued in the middle of August, had a small area of cooler than average readings in the Central Plains. A warmer than normal month is still expected in most of the West. In the east, the above average temperatures in the earlier forecast now only include Florida and Maine.
Significant changes were made to the rainfall forecast. A month of overall drier than normal weather is expected over most of the Plains. Wetter than average conditions are expected near the Four Corners and in the Ohio Valley, Middle Atlantic and the Northeast.
— NWSCPC (@NWSCPC) August 31, 2017
The Climate Prediction Center states that the September outlook was based on forecast model guidance, statistical tools, and to a lesser extent, current soil moisture conditions. EL Nino or La Nina will not be a factor since Pacific Ocean water temperatures are in a neutral state and are expected to remain that way next month. A more amplified pattern in the Jet Stream is one of the main reasons for the changes to the temperature forecast, with a slight shift eastward.
For WeatherNation: Meteorologist Mace Michaels