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.

ECM ENS identifies the wet arc of moisture through the Southwest U.S. to the Colorado Rockies and into the Midwest U.S. in the latest 15-day forecast. Interestingly, AIFS ENS is farther to the west with the arc featuring remnants of a tropical cyclone striking California early in the 11-15-day period. The strong Southwest U.S. Monsoon is inspired by an intense marine heatwave off the coast of Southwest North America.