The Climate Prediction Center (CPC) at the National Weather Service issued an updated monthly outlook for March on Tuesday evening. Warmer than normal weather is expected for much of the country, from the Southwest through the Central Plains and into the East. A small area of cooler than average conditions are expected in the Northwest. Drier than normal weather is in the forecast around the Four Corners region, with wetter than average conditions for the Great Lakes and Northwest.
— NWSCPC (@NWSCPC) March 1, 2017
There have been several changes and tweaks to the forecast from the previous outlook issued only two weeks ago. The above average temperature forecast has expanded, along with the drier than normal area. Many changes were made to the above average precipitation outlook. The cooler than normal forecast area was shifted westward.
— NWSCPC (@NWSCPC) February 16, 2017
According to the CPC, the adjustments have been “primarily based on short-, medium-, and extended-range dynamical model guidance, MJO considerations, and to a lesser degree, week 3-4 model guidance.”
The position of the Jet Stream was a factor, with a blocking pattern observed west of Alaska. The flow will affect the positioning of cold air driving into the country from the north and also higher humidity and storm track. This would favor the Pacific Northwest.
[Images courtesy of The Center for Ocean-Land-Atmosphere Studies]
The MJO (Madden-Julian Oscillation) is a large area of tropical thunderstorms that commonly occurs where sea surface temperatures are above average. The MJO area tends to move around the Earth near the equator from west to east every 1 to 2 months. The MJO is currently located in West Central Indian Ocean, favoring drying in the Four Corners region and warmer than normal weather for the central and eastern parts of the nation.
The lack of snow cover in many areas of the country, coupled with warmer than average coastal water temperatures, were also factored into the March outlook.
For WeatherNation: Meteorologist Mace Michaels