I've been watching the trends in the May forecast from the ECMWF and the story has been consistent to start the month. We are expecting a heatwave in the Pacific Northwest, wet conditions (with flooding) across the South from Texas to South Carolina, drier and colder in the Northern Plains, Midwest, Great Lakes, and Northeast, and very cold in Central Canada. The problem is that the 30-day outlook from the ECMWF through the end of May looks exactly the same. The ECMWF longer range forecast is stuck on persistence - using the predictions for the next 2 weeks as the dominant factor controlling the last two weeks of May.
What I am watching: 1. Rapid climb in equatorial Pacific Ocean temps (El Niño). 2. The Marine Heatwave that extends from the West Coast of the US and Mexico toward a region south of Hawaii (++PMM). 3. The Gulf of Alaska temperatures. In order to assess the temperature and precipitation patterns across the US for June, we need to see how these three areas change. Then we can look at the Bermuda High and examine the "Elvis Rule" to determine how June will shape up for the US. More on this soon...