“Oscar is at best barely a tropical storm at this time,” the center said.
It was expected to drop up to 5 inches (13 centimeters) of rain across the southeastern Bahamas, with up to 8 inches (20 centimeters) in isolated areas. A tropical storm warning was in effect for the central and southeastern Bahamas.
The storm made history as the smallest recorded hurricane, with a wind field of only about 6 miles (10 kilometers) across. It caught many by surprise as it made landfall in Grand Inagua Island in the Bahamas on Saturday and a second landfall in eastern Cuba late Sunday.
“It’s not often we see a colossal failure in hurricane forecasting,” Michael Lowry, a hurricane specialist and storm surge expert, wrote in an analysis. He noted no models indicated Oscar would strengthen into a hurricane.
Oscar dropped at least 15 inches (38 centimeters) of rain in parts of eastern Cuba on Monday, with forecasters warning of heavy flooding and possible landslides. The six deaths were reported in Guantánamo.
The storm hit as Cuba struggles to recover from a massive blackout that sparked a handful of small protests and a stern government warning that any unrest will be punished.
Oscar is the 15th named storm and 10th hurricane of the Atlantic hurricane season, which begins June 1 and ends Nov. 30.
The National Oceanic and Atmospheric Administration predicted an above-average Atlantic hurricane season this year because of record-warm ocean temperatures. It forecast 17 to 25 named storms before the season ends, with four to seven major hurricanes of Category 3 or higher.
Meanwhile, Tropical Storm Kristy swirled over open waters in the Pacific Ocean.
It was located 375 miles (605 kilometers) west-southwest of Acapulco, Mexico on Tuesday. It had maximum sustained winds of 50 mph (85 kph) and was moving west-northwest at 15 mph (24 kph). Kristy was expected to become a hurricane by Tuesday night.