MIAMI: Tropical Storm Isaias formed in the southwestern Gulf of Mexico on Wednesday morning and is forecast to rapidly strengthen into a dangerous hurricane as it heads toward the northern Gulf Coast, the National Hurricane Center said.
The storm had sustained winds of 40 mph and was located about 600 miles south of the mouth of the Mississippi River. It is expected to move east over Mexico's Yucatan Peninsula before turning sharply north toward the Gulf Coast as it strengthens.
Forecasters said Isaias could peak as a Category 2 hurricane with winds of 110 mph by Thursday night or early Friday before weakening slightly ahead of landfall.
Hurricane and storm surge watches — warning of winds of 74 mph or stronger and life-threatening coastal flooding within 48 hours — are likely to be issued for parts of the northern Gulf Coast on Wednesday.
The storm is expected to bring flooding rain, powerful winds and storm surge to areas from southern Louisiana to the Florida Panhandle beginning Friday, and could spawn several tornadoes as its rainbands reach the coast.
Isaias will be the first hurricane of the year in the Atlantic basin, ending a record-long wait tied to the effects of a likely record-strong El Niño.
Forecasters cautioned that the storm's exact track and strength at landfall remain uncertain, and urged residents from Louisiana to Florida's Big Bend to monitor updates closely.
Florida Gov. Ron DeSantis declared a state of emergency for 25 counties Tuesday, urging residents to prepare disaster plans and stock hurricane supply kits. State emergency teams are staging generators, fuel, food, water and flood barriers in the Tallahassee and Santa Rosa areas.
Oil companies also were taking precautions. Shell is evacuating nonessential personnel from six offshore platforms, while BP is removing nonessential workers and securing its offshore facilities, the companies said Tuesday.
The storm is moving through El Niño-influenced atmospheric conditions that have largely suppressed tropical activity in the Atlantic this season. Gulf waters are record warm for this time of year, but wind shear — winds blowing at different speeds and directions at multiple levels of the atmosphere — has been the main obstacle for storms this season and can tear systems apart.
Isaias is benefiting from low wind shear in the southern Gulf, but forecasters said it will encounter stronger shear near the Gulf Coast. Because the storm is expected to move quickly, its exposure to those hostile conditions may be limited.
The storm's strength and path are intertwined: a stronger storm's circulation reaches higher into the atmosphere, allowing upper-level winds to steer it differently than a weaker system, which in turn affects how long it spends over warm water and how much wind shear it encounters.
Regardless of its final strength, heavy rain is a concern. The storm could bring 3 to 6 inches of rain, with isolated totals up to 10 inches, from southern Louisiana to the Florida Panhandle and Big Bend. Downpours could begin along the coast Friday and continue through the weekend as the system moves inland.
This year has already shown that hurricane-strength systems are not required to cause significant damage. Tropical storms Arthur and Edouard were short-lived but produced heavy rain, flash flooding and water rescues. Parts of Louisiana and Mississippi saw flooding from Arthur, while Edouard dropped more than 20 inches of rain in eastern Texas.
Pinpointing the location and severity of storm surge, strong winds and tornadoes along the northern Gulf Coast remains difficult because the storm's strength and track are still uncertain. The earliest those impacts could arrive is Friday or early Saturday.
