At 5 a.m. Saturday, the center of the storm was about 740 miles (1,195 kilometers) east of the Leeward Islands, which include the Virgin Islands, Antigua, St. Kitts and Nevis and Anguilla.
It was moving toward the west-northwest at 10 mph (17 kph) but was expected to increase its forward speed slightly later Saturday, the center said.
Though it remained a Category 2 storm, maximum sustained winds decreased to near 100 mph (155 kph) with higher gusts, and the storm was forecast to weaken during the next 48 hours.
Danny is relatively tiny, forecasters say, with hurricane-force winds extending only 15 miles (24 km) from its center Saturday morning.
There were no weather advisories in effect for those in Danny's possible path, but the center said those in the Leeward Islands and the Virgin Islands should monitor the storm's progress. Tropical storm watches will likely be required later Saturday for those areas, it said.
The five-day National Weather Service forecast for Danny showed the center of the storm approaching the Leeward Islands early Monday, then approaching Puerto Rico early Tuesday. The storm's center could hit the Dominican Republic early Wednesday and the eastern part of Cuba on Thursday, according to the forecast.
Danny is expected to continue losing strength during the next several days, especially as it reaches land, the National Hurricane Center said in a forecast discussion early Saturday.
Kilo weakens south of Hawaii
Meanwhile, Tropical Storm Kilo in the Pacific returned to tropical depression status overnight, about 450 miles (725 km) south-soutwest of Hilo, Hawaii, according to the Central Pacific Hurricane Center
The revised forecast showed it strengthening into a hurricane on Tuesday evening.
Kilo was moving slowly to the west at about 16 mph (26 kph). It was forecast to make a turn to the north on Sunday night and head toward the Hawaiian Islands Monday night, the center said.
Kilo's maximum sustained winds were 36 mph (56 kph) with higher gusts.
The U.S. Air Force was conducting regular flights into the storm to gather information about its structure and intensity, the center said. The 53rd Weather Reconnaissance Squadron
, known as the Hurricane Hunters, are based at Keesler Air Force Base in Biloxi, Mississippi, and provides surveillance of tropical storms and hurricanes for the National Hurricane Center.
El Niño's effect on Atlantic hurricanes
Hurricane Arthur, a Category 2 storm, was the last hurricane to make landfall in the United States when it came ashore in July 2014 between Cape Lookout and Beaufort, North Carolina, the National Hurricane Center said.
Though forecasters are calling for a below-average storm season in the Atlantic, Hennen said any hurricane that does emerge this year can have a strong impact.
Hurricane Andrew struck South Florida and south-central Louisiana in August 1992 with 175-mph winds, wiping out entire communities, killing 23 people and causing more than $25 billion in damage.
According to the National Oceanic and Atmospheric Administration Climate Prediction Center
, which has updated its 2015 Atlantic hurricane season outlook, there is a 90% chance of a below-normal hurricane season and a lower chance of expected storm activity in the United States this year.
Of the six to 10 named storms for this season, one to four storms are likely to become hurricanes in 2015.
There's an even smaller chance that one of these storms will transform into a major hurricane. The National Hurricane Center calls any Category 3 or higher storm a major hurricane.
Also, the Atlantic Ocean has had much cooler temperatures, which decreases the chances of major storm activity.
Since 1995, the United States has been in a high hurricane activity area, which typically lasts around 25 years. But for almost a decade, the country hasn't seen a hurricane greater than a Category 3 storm, putting it in a nine-year major hurricane "drought."
It has been the longest period to pass without a major hurricane hitting the United States since reliable record-keeping began in 1850, a 2015 NASA study said.
The United States still has seen some big storms in the past few years. In 2012, hurricane-turned-cyclone Superstorm Sandy ravaged the Northeast with damaging flooding and powerful winds.