Weekend forecasts maintain the stratospheric warming episode unfolding on the Eurasian side of the North Pole in the short-term and gradually extending across the polar region in the 15-day outlook. The Graph Cast 500 MB anomaly forecast indicates a polar vortex pattern forms on the Northeast Canada Coast with moderate intensity troughs located in Alaska and the West U.S.

The daily Nino12 SSTA roars to +1.36C and is nearly 2C warmer than 30 days ago. The 2024-45 La Nina appears short-lived! The much warmer change is driven by effects from a recent Madden Julian oscillation regime.

Four forecast models are considered to offer a broad view of forecast skill during the past 60 days for the northern hemisphere, North America, and Europe. The four processed considered are two physics-based models: ECM ENS and GFS plus two AI models: AI Graph Cast ECM ENS and AIFS. ECM ENS is selected due to the consistent highest skill score while GFS is reviewed due to high visibility.

During recent weeks, the convection phase of the Madden Julian oscillation (MJO) settled in the eastern equatorial Pacific to the longitudes of the Americas. Consequently, trade winds have eased across the eastern equatorial Pacific Ocean preventing the upwelling of cooler waters to sustain La Nina. The Nino SSTA regions have warmed significantly.