National Aeronautics Space Administration satellite data has shown that the Hurricane Irene's diameter is about one-third the length of the United States Atlantic coastline.
It also discovered that tenth tropical depression has formed to the east off the African coast.
Tropical Depression 10 formed about 435 miles west-southwest of the southernmost Cape Verde Islands.
It was centered near 12.4 North and 30.4 West, and moving to the west-northwest near 13 metre per hour.
NASA satellites flying above Hurricane Irene, are providing forecasters temperature, pressure, wind, and cloud and sea surface temperature data which would help determine Irene's behaviour and track.
The National Hurricane Center (NHC) has issued a hurricane warning for the central and northwestern Bahamas and the U.S. east coast.
A tropical storm watch is in effect for north of Edisto Beach, South Carolina to Surf City North Carolina.
Warnings of dangerous rip currents and high surf along the eastern shores have also been issued to the South Florida residents.
A tropical storm warning in effect for Palm Beach County marine waters Florida beyond 20 nautical miles.
Also, evacuation plans are already underway in North Carolina to protect the residents.(ANI)