its extremely wide swath of hurricane force winds extended at least 75 nautical miles (138 km) to the east
from the center.
Katrina initially formed about 200 miles (322 km) southeast of the Bahamas on Aug. 23, 2005, as a
tropical depression, according to the NOAA. A well-defined band of storm clouds began to wrap around
the north side of the storm's circulation center in the early morning hours of Aug. 24. With winds of about
40 mph (65 kph), the storm was named Tropical hurricane Katrina.By the time it made its way to southern
Florida on Aug. 25, Katrina was a moderate Category 1 hurricane. While it caused some flooding and
casualties — two people were killed — during its first landfall, it appeared to be just another hurricane in
an active hurricane season. Katrina weakened after passing over Florida and was reclassified as a tropical
storm.
But, once over water again, Katrina stalled beneath a very large upper-level anticyclone that dominated
the entire Gulf of Mexico, and rapidly gained strength. Katrina re-intensified into a hurricane on Aug. 26,
and became a Category Five storm on Aug. 28, with winds blowing at about 175 mph (280 kph). The
storm turned north toward the Louisiana coast. The storm weakened to a Category 3 storm before making
landfall along the Louisiana-Mississippi border on the morning of Aug. 29 with sustained winds of 120
