Scientists stress, however, that ocean conditions alone do not guarantee a Super El Niño will develop. What Is a Super El Niño? A Super El Niño is an informal scientific term describing exceptionally strong events in which ocean temperatures exceed approximately 2°C above average. What the US Winter Weather Forecast SuggestsHistorical El Niño winters have often produced distinct regional weather patterns across the United States. Whether that ultimately produces a powerful El Niño or simply a more moderate event will become clearer as autumn approaches and the 2026 US winter weather forecast continues to evolve.