The (Long Paddock) daily southern oscillation index (SOI) can tell us something about the atmospheric reaction to what’s going on within the ENSO System. El Nino ended recently, and neutral ENSO is in-place. We’re awaiting a transition to La Nina during the second half of the year although confidence in timing is LOW.

A combination of new and established marine heat waves were significant contributors to an upper air pattern responsible for delivering historic flooding in far southeastern Brazil and equally impressive cold in Western Russia during the past 2-3 weeks. An emerging and progressive convection phase of the Madden Julian oscillation should ease this pattern during late May.

High pressure is forecast to extend across much of the West U.S. during JUN/JUL 2024 with a weak upper trough in the East. The combination of these two pressure centers will leave most of the U.S. with below normal wind speeds for the first half of summer 2024. There are a few exceptions such as Northern California, Southern Texas, and the Carolinas where wind speeds are greater than normal.

Last week the Nino34 SSTA dipped below the (+0.5C) El Nino threshold. ENSO is now officially in neutral phase. Only the Nino4 SSTA region (near the Dateline) is above the El Nino threshold.