Colorado State University researchers have lowered their 2026 Atlantic hurricane season forecast for a second time, now projecting nine named storms, four hurricanes and one major hurricane as confidence grows that a strong or very strong El Niño will suppress activity during the season’s peak.
The July outlook represents a further reduction from the university’s initial April 9 forecast of 13 named storms, six hurricanes and two major hurricanes. CSU lowered those projections on June 10 to 11 named storms, five hurricanes and two major hurricanes before issuing the latest revision.
One named storm had formed through July 7, leaving eight named storms, four hurricanes and one major hurricane forecast for the remainder of the season.
The latest outlook calls for what researchers described as a “well below-normal season,” with each principal measure of expected activity falling below its 1991–2020 average.
CSU now projects:
- Nine named storms, compared with the average of 14.4.
- Thirty-five named storm days, compared with 69.4.
- Four hurricanes, compared with 7.2.
- Twelve hurricane days, compared with 27.
- One major hurricane, compared with 3.2.
- Two major hurricane days, compared with 7.4.
- Accumulated Cyclone Energy of 50, compared with the average of 123.
- Accumulated Cyclone Energy west of 60 degrees longitude of 25, compared with 73.
Accumulated Cyclone Energy, or ACE, measures a named storm’s potential for wind and storm-surge destruction. It is calculated using the square of a storm’s maximum sustained wind speed during each six-hour period of its existence.
The forecast ACE of 50 and overall Net Tropical Cyclone Activity of 60 represent approximately 40 to 45 percent of their long-term averages.
Caribbean Major-Hurricane Probability Falls Below Historical Average
CSU estimates a 19 percent chance of at least one major hurricane tracking through the Caribbean after July 7. The historical average for the region is 47 percent.
The probability of at least one major hurricane making landfall along the entire continental United States coastline is estimated at 17 percent, compared with a historical average of 43 percent.
The probability is 8 percent for the U.S. East Coast, including the Florida peninsula, compared with an average of 21 percent. For the Gulf Coast, the forecast probability is 10 percent, compared with the historical average of 27 percent.
The seasonal forecast does not predict where an individual storm will form, travel or make landfall. Researchers cautioned that lower projected activity does not eliminate the possibility of a destructive hurricane affecting the Virgin Islands or another specific location.
“As with all hurricane seasons, coastal residents are reminded that it only takes one hurricane making landfall to make it an active season. Thorough preparations should be made every season, regardless of predicted activity.”
Strengthening El Niño Expected to Increase Wind Shear
The downward revision is primarily based on growing confidence that the moderate El Niño currently present in the tropical Pacific will strengthen during the coming months and could become strong or very strong during the August-through-October peak of hurricane season.
El Niño typically increases vertical wind shear across the tropical Atlantic and Caribbean. Wind shear refers to differences in wind speed or direction at varying levels of the atmosphere and can disrupt the formation and strengthening of tropical cyclones.
Sea-surface temperatures across most of the Caribbean and tropical Atlantic are near their long-term averages. Trade winds across much of the region have also been somewhat stronger than average, limiting additional ocean warming.
CSU expects El Niño to become the dominant influence on the season, producing high levels of vertical wind shear across the tropical Atlantic and Caribbean. Vertical wind shear has already been elevated over the Caribbean in recent weeks and is forecast to remain highly elevated in the near term.
Although the eastern subtropical Atlantic has been much warmer than normal, the absence of unusual warmth across the tropical Atlantic and Caribbean is considered unfavorable for an active season.
Forecast Includes Statistical, Global and AI-Based Guidance
The July outlook combines a statistical prediction model, statistical and dynamical models, historical analog seasons, qualitative adjustments and, for the first time, output from the Ai2 Climate Emulator, an artificial intelligence-based atmospheric model.
The statistical forecast uses approximately 40 years of previous data. The dynamical guidance includes models from the European Centre for Medium-Range Weather Forecasts, the United Kingdom Met Office, the Japan Meteorological Agency and the Centro Euro-Mediterraneo sui Cambiamenti Climatici.
Researchers said the majority of the model guidance supports a below-normal season. The forecast gives greater weight to the lower projections produced by the historical analog seasons and the ECMWF and CMCC models because of the high likelihood of a powerful El Niño during the season’s peak.
The six historical seasons selected as the closest comparisons to projected 2026 conditions were 1965, 1982, 1987, 1997, 2009 and 2015. Those years generally featured strong El Niño conditions and near-average tropical Atlantic temperatures.
Forecast Retains a Range of Uncertainty
Although the central forecast calls for nine named storms, CSU calculated a likely range of seven to 11. The projected range is two to six hurricanes and zero to two major hurricanes.
The uncertainty range for total ACE is 25 to 85, while ACE west of 60 degrees longitude could range from 11 to 47.
CSU plans to release its final seasonal update on August 5. The university will also begin issuing two-week Atlantic tropical cyclone activity forecasts that day. A review and verification of its 2026 forecasts is scheduled for November 24.
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