The unusually warm Gulf of Mexico SST of Q1/2023 increased low-level atmospheric moisture that when entrained into mid-latitude synoptic storms, caused excessive rainfall and unusually intense severe weather. However, the increase in southern latitude storm track intensity inspired by transient Pacific MJO episodes in March and April has caused a steady loss of upper ocean heat in the Gulf of Mexico in recent weeks. The 30-day SSTA change in the Gulf of Mexico is nearly 1C.

Another Madden Julian oscillation (MJO) surge toward the Dateline in the equatorial Pacific the next 2 weeks could cause the onset of El Nino, warms the eastern U.S., and soaks the southern Great Plains and Mid-south States.

During the past week, rainfall required to end dry Palmer Drought Severity Index (PDSI) increased in western Kansas, eastern Colorado, and southwest Texas while the remainder of the Great Plains drought area remain unchanged although shifting wetter in the Houston Area on the Texas Coast. The Mid-Atlantic drought worsened. Rainfall needed to end drought in northern Virginia/Washington D.C. is now in the 12-15 in. range.

Almost the entire equatorial Pacific Ocean is warmer than normal in the subsurface (upper ocean heat) except to the immediate east of the Dateline. The warming during the past 2-3 weeks is dramatic with a big assist from the Madden Julian oscillation and an eastward surging Kelvin Wave. Despite the eastern equatorial Pacific subsurface warming, the bulk of the upper ocean heat remains west of the Dateline as ENSO 2023 is looking more complicated.