Colorado State University (CSU) researchers are forecasting a somewhat below-average Atlantic hurricane season in 2026, citing the expected development of El Niño conditions that typically suppress storm formation in the basin.
In their initial seasonal outlook, released Thursday, the CSU team projected 13 named storms during the June 1 to Nov. 30 Atlantic season, including six hurricanes and two major hurricanes of Category 3 strength or higher. That compares with long-term averages of 14.4 named storms, 7.2 hurricanes and 3.2 major hurricanes.
The forecast also calls for 55 named storm days, 20 hurricane days and five major hurricane days, all below historical averages. Researchers projected accumulated cyclone energy, a metric used to measure the combined strength and duration of storms, at 90, compared with a long-term average of 123.
The main factor behind the outlook is the expected shift from weak La Niña conditions in the tropical Pacific to a moderate or strong El Niño by the peak of the Atlantic season from August through October. El Niño tends to strengthen upper-level westerly winds across the Caribbean and tropical Atlantic, increasing vertical wind shear that can disrupt hurricane formation and intensification.
At the same time, the Atlantic is showing mixed signals. Waters in the western tropical Atlantic are warmer than normal, a condition that can support storm development, while waters in the eastern tropical and subtropical Atlantic are slightly cooler than normal, which can have the opposite effect.
The CSU team said the forecast is based on a statistical model and several additional models using historical hurricane data and projected large-scale atmospheric and ocean conditions from international forecasting centers. This year’s outlook also incorporates, for the first time, a machine learning-based climate model called the Ai2 Climate Emulator. While the statistical model pointed to a slightly above-average season, the other model guidance generally favored somewhat below-average activity.
Researchers said the early April forecast carries substantial uncertainty because oceanic and atmospheric conditions can change considerably before the season reaches its peak. The report compared 2026 to analog years including 2006, 2009, 2015 and 2023, but noted that those seasons produced a wide range of outcomes.
CSU estimated that 2026 activity will reach about 75% of the average season from 1991 to 2020. For comparison, the report said 2025 hurricane activity was about 105% of average.
The outlook also included below-average landfall probabilities for major hurricanes: 32% for the entire U.S. coastline, 15% for the East Coast including the Florida Peninsula, 20% for the Gulf Coast from the Florida Panhandle to Brownsville, Texas, and 35% for the Caribbean.
CSU plans forecast updates on June 10, July 8 and Aug. 5.
