How El Niño is playing a role in Hurricane Isaias

Isaias, the first hurricane of the Atlantic season, was expected to gain strength as it approached Florida, Alabama and Mississippi coasts Thursday. Mandatory evacuations and school closures were issued in parts of Florida. The storm was predicted to bring intense winds and a dangerous storm surge to the northern Gulf Coast late Friday or early Saturday, along with the potential for heavy rain and flooding into the weekend as far inland as the Tennessee Valley.

The hurricane had maximum sustained winds of about 80 mph (129 kph) and was moving east-northeast at a speed of 9 mph (15 kph). Coastal communities were swift to prepare, with some Gulf oil wells pausing production and at least four Florida school districts canceling classes. Governors in Florida and Alabama declared emergency states for numerous counties.

The National Weather Service warned communities from Mississippi to Florida to get ready for the possibility of "prolonged power outages." Isaias formed late in the season, tying a 121-year-old record for the area's latest-forming hurricane. The Atlantic hurricane season had been relatively calm this year due to a strong El Niño, which disrupts storm formation.

Isaias was expected to impact an area familiar with major hurricanes, such as Hurricane Camille in 1969 and Hurricane Katrina in 2005. Oil production and tourism were already affected, with offshore production shutting down and about 25% of the oil production in the region temporarily halted. The storm could also disrupt a college football game between rivals Georgia and Alabama, which President Trump was planning to attend.

Alabama and Florida authorities urged residents in low-lying areas to voluntarily evacuate, and city officials in Pensacola prepared to quickly repair power outages.