The Nino34 SSTA located in the east-central equatorial Pacific Ocean warmed to +0.3C last week. The 30-day southern oscillation index (SOI) average is an El Nino-like -0.66 and projected to finish June at the -0.50 El Nino threshold. Upper ocean heat in the equatorial Pacific was at a cool peak, supportive of La Nina development 2-3 months ago. Since that time the cool anomaly to support La Nina has lost half of its intensity.

The recent heavy rainfall event across Southern Florida shifting westward and into Texas enhanced by Tropical Storm Alberto created plentiful cloudiness, rainfall, and windy conditions to cause the Gulf of Mexico basin to cool to near normal. The 30-day change in Gulf of Mexico basin SST is a remarkable -1.08C.

NOAA/CPC probabilistic climate forecasts indicate several high impact hazards ahead for mid-to-late summer 2024. Most striking is the strong probability of persistent heat across the eastern third of the U.S. and Interior West during July.

The historic rainfall flooding Southern Florida during the past week is easing. “Historic” in that the extreme rain was not associated with a tropical cyclone. The low-pressure zone and wet trade winds are shifting westward this week. However, this time a tropical cyclone will enhance the rainfall and bring flooding to the northwest and west coast of the Gulf of Mexico.