Twenty named storms churned in the Atlantic basin during the 2023 hurricane season.
Forecasters predicted an above-normal season and that’s what the region experienced June 1-Nov. 30.
With 20 named storms, the season saw the fourth most storms since 1950.
Seven of the 20 named storms were hurricanes and three intensified to major hurricanes — category 3 or higher on the Saffir-Simpson Hurricane Wind Scale.
An average season produces 14 named storms, seven hurricanes and three major hurricanes.
“A strong El Nino and record warm water in the tropical Atlantic were competing factors and the main drivers of hurricane activity this season,” Matthew Rosencrans, lead hurricane forecaster at NOAA’s Climate Prediction Center, said in a news release. “Based on the high number of named storms this year, I’d say the warm ocean temperatures won out.”
Hurricane Idalia, which formed in the northwestern Caribbean, intensified into a Category 4 hurricane before making landfall as a category-3 hurricane Aug. 30 near Florida’s Keaton Beach.
Idalia was the only U.S. landfalling hurricane in 2023 and it caused storm surge inundation of 7-12 feet, as well as widespread rainfall flooding in Florida and throughout the southeast.
In anticipation of Idalia, Anna Maria Island residents were ordered to evacuate Aug. 28.
“Our primary concern at this point is storm surge,” Manatee County Commission Chair Kevin Van Ostenbridge said at the time. “Coastal residents need to heed our warnings.”
In Manatee, rainfall associated with Idalia was estimated at 3-4.5 inches and the highest wind gusts were estimated at 67 mph and sustained winds at 37 mph, according to the National Weather Service.
Local storm surge was at 3-7 feet, as Idalia’s impact on the coast was compounded by king tides Aug. 30.
Returning to the coast Aug. 30, island residents and business owners found re-sculpted shorelines, debris littered yards, flooded roads and parking lots and some water intrusion in structures.
Manatee’s preliminary countywide damage estimate exceeded $2 million but there were no injuries reported.
Other storms with U.S. impact included:
- Tropical Storm Ophelia, which made landfall Sept. 23 with 70-mph winds on Emerald Island, North Carolina, causing widespread heavy rainfall, gusty winds and significant river and storm surge flooding in portions of eastern North Carolina.
- Hurricane Lee, which made landfall as a post-tropical cyclone in Nova Scotia, Canada, Sept. 16. Swells generated by Lee caused dangerous surf and rip currents along the entire U.S. Atlantic coast. Strong winds with hurricane‑force gusts from Lee caused extensive power outages in Maine and in parts of Canada.
“The Atlantic basin produced the most named storms of any El Nino-influenced year in the modern record,” said Rosencrans. “The record warm ocean temperatures in the Atlantic provided a strong counterbalance to the traditional El Nino impacts.”
A new analysis and forecast system helped National Hurricane Center forecasters improve intensity predictions this season, according to the release.
Intensity forecasts showed Idalia as a major hurricane impacting the coast of Florida from early Aug. 28 through landfall two days later.
The lead time gave people in threatened areas more time to prepare and respond and there were no storm surge fatalities from Idalia despite storm surge inundation of as much as 12 feet above ground level in some areas.
Further, extending the hurricane center’s tropical weather outlook from five to seven days provided emergency managers more time to prepare.