Hurricane Isaias strengthens to category 3 before making landfall in the southern United States

Hurricane Isaias strengthened on Friday into a “major” Category 3 hurricane on a scale of five as it approached the southern United States, which it could hit head-on in the evening or Saturday morning. With sustained winds of 195 km/h, Isaias now reaches Category 3 on the Saffir-Simpson scale, announced the US National Hurricane Center (NHC).

It is expected to make landfall in Florida, Alabama or Mississippi between Friday evening and Saturday, according to American meteorologists, bringing destructive winds, violent waves and colossal rains which raise fears of significant flooding and property damage. Faced with the risks, the American authorities have already announced the first evacuations in coastal areas and expect serious disruptions in the hydrocarbon sector in the Gulf of Mexico.

“We are taking this storm very, very seriously,” Florida Governor Ron DeSantis assured Friday morning during a press conference, saying he expected “considerable damage” on the coast. Isaias is the first hurricane of the season in the Atlantic, where cyclonic activity, which began on June 1 and lasts until the end of November, has been unusually calm due to the El Niño climatic phenomenon.

El Niño modifies atmospheric circulation on a large scale, with opposite effects around the globe. In the tropical Atlantic, it tends to strengthen wind shear, which blocks the formation of cyclones despite very warm oceans. “Isaias will be a dangerous hurricane, with significant storm surge, damaging winds and flooding caused by precipitation when it reaches the northern shore of the Gulf of Mexico, between Friday and Saturday,” warned the United States National Weather Service.

Several airports in Florida have planned to temporarily stop flights and many oil platforms, notably belonging to the Chevron and Shell companies, should be evacuated. About two-thirds of the region's oil production capacity and more than half of its gas production capacity are suspended, according to data released Thursday by the U.S. Oil, Natural Gas and Minerals Administration. Or nearly 1.3 million barrels per day removed from the world market.

Regions on Isaias' path could see 10 to 20 centimeters of precipitation, with peaks reaching 38 centimeters in some areas, experts have warned. The U.S. National Weather Service called on residents in areas likely to be affected to “promptly complete” preparations to protect buildings from rising waters and strong winds.