Mexico, Caribbean Sea, and western North Atlantic basin are moderately warmer than normal with little recent change. In the tropics, SSTA is near normal in the central basin with sharp warming off the West Africa Coast. Upper ocean heat in the deep tropics is near normal given the 2013-25 available climatology. Interestingly, upper ocean heat in the Gulf of Mexico has plummeted to lowest levels on record given the 2013-25 climatology.

The most recent ECMWF relative Nino34 SSTA index forecast maintains a projection of record-strength El Nino for late 2026 into early 2027. The NCEP CFS V2 forecast also projects record setting +3.5 for Nino34 SSTA during late 2026.

Titanic high pressure triggers a severe heatwave centered on the Mid-south to Southeast U.S. through next week. The last week of August finds the high pressure broadening but losing intensity across the southeast quadrant of the U.S. The upper trough over Southeast Canada strengthens and in response, upstream ridge in Western Canada amplifies. The Western Canada ridge becomes a dominating upper feature in early September.

Historically, major hurricanes observed during AUG/SEP/OCT of strong El Nino years are minimal. Only 1 of 5 analog years produced 2 major hurricanes (2015) possibly related to a warmer North Atlantic basin. In 2026, the North Atlantic basin is projected twice as warm as 2015. Notable storms were Joaquin (2015) and Betsy (1965) for having southwesterly tracks into warmer ocean water to cause significant strengthening as westerly El Nino shear failed to turn these storms northward.