Tropical Storm Isaias Heads for the Gulf Coast After a Late, Quiet Start to Hurricane Season

Tropical Storm Isaias formed in the Gulf on Wednesday and is forecast to become the first hurricane of the Atlantic season before approaching the northern Gulf Coast late this week, according to the National Hurricane Center. Residents from Louisiana to the Florida Panhandle have been urged to review their hurricane plans.

The storm grew from Tropical Depression Nine. CBS News reported that Isaias is the ninth named storm of the season and is expected to strengthen rapidly.

Where Isaias is and where it is headed

ABC News, citing the hurricane center, reported that the storm was centered about 285 miles west of Progreso, Mexico, and about 580 miles southwest of the mouth of the Mississippi River. Its maximum sustained winds were 40 mph, and it was moving east-northeast at 8 mph.

Forecasters expect it to pass north of Mexico's Yucatan Peninsula on Thursday, CBS News reported. The hurricane center's initial projections put the center coming ashore late Friday or early Saturday somewhere between eastern Louisiana and the western Florida Panhandle, according to ABC News. The exact landfall location was not yet known.

Why it matters: rain, wind and surge risks

The hurricane center warned of an increasing risk of dangerous wind and storm surge along parts of the northern Gulf Coast. It urged people in Louisiana, Alabama, Mississippi and northern Florida to follow forecast updates closely.

According to the hurricane center, as cited by CBS News and The Guardian, the central Gulf Coast from southeastern Louisiana to the Florida Panhandle could see 3 to 6 inches of rain, with as much as 10 inches in some places. Urban flooding and isolated river flooding are possible. CBS News said moderate to heavy rain could spread across the Southeast this weekend into early next week, and some longer-range models bring the moisture to the Ohio Valley and Northeast by midweek.

The Guardian, citing AccuWeather, reported that if the system reaches hurricane strength, gusts of 60-80 mph could occur near the center, with stronger gusts possible. Dangerous surf and rip currents are also expected. AccuWeather expert Alex DaSilva said the storm should avoid the strongest wind shear until late in the week, when it should begin to lose intensity as it nears the coast.

Emergency declarations

Florida Gov. Ron DeSantis signed an executive order declaring a state of emergency for 25 counties in the Panhandle and Big Bend regions. ABC News said the declaration activates the state's emergency management plan and allows actions such as deploying personnel and equipment. DeSantis said in a statement that it gives communities time and resources to prepare.

A late first hurricane in a quiet season

The Guardian, citing the Associated Press, reported that a first hurricane has not formed this late in the Atlantic season since Oct. 8, 1905. The season ends Nov. 30. Sources attribute the quiet Atlantic to a strong El Niño, which increases wind shear over the Atlantic and can keep tropical storms from becoming hurricanes. The same pattern has been linked to above-average activity in the Pacific.

Separately, The Guardian reported that heavy rain from a different tropical wave triggered flooding and landslides in St Vincent and the Grenadines, where schools were closed Tuesday.

What to watch next

CBS News reported the hurricane center said hurricane watches would likely be needed for part of the northern Gulf Coast. Forecasts for strength and landfall are likely to be refined as the storm moves across the Gulf.

Sources: The Guardian, CBS News, ABC News