On July 10, a tropical wave exited the African coast and moved westward over the open Atlantic for several days.
Initially, the associated weather activity was limited to weak showers, and environmental conditions were not forecast to become conducive for significant organization.
Although upper-level wind shear remained somewhat adverse, a process of slow development became evident by July 19 as surface pressures began to fall.
The wave proceeded along the extreme northeastern Caribbean, where convective activity waxed and waned due to periods of variable wind shear and brief land interaction with Hispaniola.
By July 22, thundershower activity reestablished over the Bahamas, with a distinct area of low pressure centered between the islands of Acklins and Great Inagua.
Satellite observations confirmed a closed circulation, leading the National Hurricane Center (NHC) to issue the formation of Tropical Depression Three around 1500 UTC.
However, post-storm analysis indicated that a depression had developed nine hours earlier than operationally confirmed.
Upon its formation, the depression was forecast to be steered to the west-northwest along a well-established subtropical ridge.
Later that day, minimum pressure dropped to 1006 mbar (29.74 inHg), and satellite imagery showed an establishment of favorable outflow in nearly all quadrants.
Although its cloud pattern remained disorganized—with the circulation center disassociated from the deepest convection—a reconnaissance aircraft flight into the cyclone found that the winds had increased.
It was therefore upgraded to Tropical Storm Bonnie southeast of Nassau, Bahamas, about five hours after NHC initiated advisories on the system.

Around 2100 UTC, Bonnie moved over Ragged Island in the Bahamas with winds of 40 mph (65 km/h), and shortly thereafter it attained its peak intensity with maximum sustained winds of 45 mph (75 km/h).
Due to increasingly  unfavorable conditions aloft, little change in intensity occurred during the following day as the storm accelerated toward Florida.
Though tropical storm-force winds prevailed, they were confined to a few rainbands to the north and east of the center at that time, with the deepest convection dislocated over southeast Florida.
On July 23 at 1430 UTC, the center of Bonnie made landfall near Elliott Key with winds of 40 mph (65 km/h).
Interaction with land caused the organization to deteriorate further, and its corresponding convection quickly diminished.
In addition, a second reconnaissance flight affirmed a lack of significant winds; it is estimated the cyclone lost tropical storm status around 1800 UTC that same day.
On the morning of July 24, deep convection briefly redeveloped over the center as Bonnie emerged into the Gulf of Mexico.
Despite the redevelopment, the storm subsequently entered a region of intense upper-level winds, causing associated convection to become sheared away rapidly.
Embedded within a well-established steering flow, Bonnie further degenerated to a tight swirl of low clouds, with no more than a few remaining patches of strong thunderstorms.
Subsequent satellite images confirmed Bonnie no longer maintained a definable structure; following the final advisory by the NHC, the system was pronounced dissipated while located about 100 mi (160 km) from the mouth of the Mississippi River.
The remnant low of Bonnie drifted west-northwestward before dissolving over southeast Louisiana on July 25.
On July 10, a tropical wave exited the African coast and moved westward over the open Atlantic for several days. Initially, the associated weather activity was limited to weak showers, and environmental conditions were not forecast to become conducive for significant organization. Although upper-level wind shear remained somewhat adverse, a process of slow development became evident by July 19 as surface pressures began to fall. The wave proceeded along the extreme northeastern Caribbean, where convective activity waxed and waned due to periods of variable wind shear and brief land interaction with Hispaniola. By July 22, thundershower activity reestablished over the Bahamas, with a distinct area of low pressure centered between the islands of Acklins and Great Inagua. Satellite observations confirmed a closed circulation, leading the National Hurricane Center (NHC) to issue the formation of Tropical Depression Three around 1500 UTC. However, post-storm analysis indicated that a depression had developed nine hours earlier than operationally confirmed. Upon its formation, the depression was forecast to be steered to the west-northwest along a well-established subtropical ridge. Later that day, minimum pressure dropped to 1006 mbar (29.74 inHg), and satellite imagery showed an establishment of favorable outflow in nearly all quadrants. Although its cloud pattern remained disorganized—with the circulation center disassociated from the deepest convection—a reconnaissance aircraft flight into the cyclone found that the winds had increased. It was therefore upgraded to Tropical Storm Bonnie southeast of Nassau, Bahamas, about five hours after NHC initiated advisories on the system.
Around 2100 UTC, Bonnie moved over Ragged Island in the Bahamas with winds of 40 mph (65 km/h), and shortly thereafter it attained its peak intensity with maximum sustained winds of 45 mph (75 km/h). Due to increasingly  unfavorable conditions aloft, little change in intensity occurred during the following day as the storm accelerated toward Florida. Though tropical storm-force winds prevailed, they were confined to a few rainbands to the north and east of the center at that time, with the deepest convection dislocated over southeast Florida. On July 23 at 1430 UTC, the center of Bonnie made landfall near Elliott Key with winds of 40 mph (65 km/h). Interaction with land caused the organization to deteriorate further, and its corresponding convection quickly diminished. In addition, a second reconnaissance flight affirmed a lack of significant winds; it is estimated the cyclone lost tropical storm status around 1800 UTC that same day. On the morning of July 24, deep convection briefly redeveloped over the center as Bonnie emerged into the Gulf of Mexico. Despite the redevelopment, the storm subsequently entered a region of intense upper-level winds, causing associated convection to become sheared away rapidly. Embedded within a well-established steering flow, Bonnie further degenerated to a tight swirl of low clouds, with no more than a few remaining patches of strong thunderstorms. Subsequent satellite images confirmed Bonnie no longer maintained a definable structure; following the final advisory by the NHC, the system was pronounced dissipated while located about 100 mi (160 km) from the mouth of the Mississippi River. The remnant low of Bonnie drifted west-northwestward before dissolving over southeast Louisiana on July 25.
Tropical Storm Bonnie (2010)