Hurricane Oscar develops in the Atlantic, featuring unexpectedly strong winds.

 A storm system in the Caribbean swiftly intensified from a tropical storm to Hurricane Oscar on Saturday, becoming the 10th hurricane of the 2024 Atlantic hurricane season.

Forecasters announced Oscar as a hurricane at 2 p.m. ET, noting that its winds were significantly stronger than earlier estimates, with maximum sustained winds reaching around 80 mph, accompanied by even stronger gusts. This rapid intensification was "unexpected," and forecasters indicated that Oscar could continue to strengthen throughout Saturday before gradually weakening next week.

The National Weather Service in Melbourne, Florida, warned that Oscar could indirectly impact East Coast beaches in the U.S. with a prolonged swell in the coming days.

Oscar also set a record by becoming the eighth named storm to form since September 24, breaking the previous record for most named storms during this period, which was established in 1950, according to Phil Klotzbach, a senior research scientist at Colorado State University.

Hurricane warnings were issued for the Turks and Caicos Islands and the southeastern Bahamas, while Cuba announced hurricane watches for the provinces of Guantanamo, Holguin, and Las Tunas.

In a separate development, Tropical Storm Nadine made landfall in Belize around noon ET on Saturday, with maximum sustained winds of 50 mph reported by the National Hurricane Center. Tropical storm warnings were in effect for Belize City and regions from Belize to Cancun, including Cozumel. With rainfall amounts expected to range from 4 to 8 inches, localized flash flooding is anticipated across southern Mexico, northern Guatemala, and northern Belize.

Tropical storm conditions are expected along parts of the Belize coast and the Yucatan Peninsula through Saturday afternoon, with isolated rainfall amounts exceeding 12 inches possible through late Tuesday. Nadine poses no threat to the U.S. as it is expected to weaken and likely dissipate over southeastern Mexico by early Sunday.

As of Saturday afternoon, Hurricane Oscar was located about 165 miles east-southeast of the southeastern Bahamas, moving west at 12 mph. It is expected to undergo some intensification before gradually slowing and turning to the west-southwest over the next couple of days. Oscar may stall near the northeastern coast of Cuba within 36 to 48 hours, bringing tropical storm conditions to parts of the southeastern Bahamas, Turks and Caicos Islands, and eastern Cuba in the next day. Heavy rainfall is forecast to begin Saturday and continue overnight, while the hurricane center warned of a "dangerous" storm surge, leading to coastal flooding in the Turks and Caicos Islands with water levels rising 2 to 4 feet.

Hurricane Oscar’s rapid development caught forecasters by surprise. Over the past week, the National Hurricane Center had been monitoring an unorganized area of showers in the Atlantic, fluctuating in its chances of development. On Saturday morning, satellite images revealed that the storm had suddenly organized, prompting a warning from the hurricane center just before 8 a.m. that it had a 60% chance of becoming a named storm later that day.

By 11 a.m., the hurricane center began issuing advisories for Tropical Storm Oscar, and just three hours later, it was upgraded to a hurricane after an Air Force Reserve Hurricane Hunter flight confirmed an eye, declining pressure, and hurricane-force winds. Notably, Oscar's winds increased by 40 mph in that short period. Despite this rapid intensification, Oscar remains a small storm, with hurricane-force winds extending only up to 5 miles from its center and a mean diameter of around 80 miles.

Oscar marks at least the fifth hurricane this year to experience rapid intensification, a phenomenon characterized by winds increasing at least 35 mph within 24 hours. This rapid strengthening is facilitated by favorable conditions such as warm ocean waters and low wind shear, with the Caribbean and surrounding Atlantic waters being warmer than normal this season. Other storms this year, including Hurricane Beryl and Milton, also saw dramatic increases in wind speeds in very short timeframes.