Danny ultimately only brought light rain to the region, with its effects considered beneficial due to a severe drought.

On August 14, 2015, a well-defined tropical wave, accompanied by significant surface pressure falls, traversed Western Africa and emerged over the Atlantic Ocean that evening.

[2] Embedded within monsoon flow,[4] various environmental factors enabled gradual development of the disturbance, including low wind shear, above-average sea surface temperatures,[2] moderate moisture content, and favorable diffluence.

[7] A temporary intrusion of dry air caused convection to collapse later that day,[8] but cloud cover redeveloped within hours.

[9] Improving upper-level outflow supported the formation of a central dense overcast and a 12 mi (19 km) wide-eye soon developed.

[12] An unusually small hurricane,[13] with gale-force winds extending only 60 mi (95 km) from its center,[14] Danny was prone to significant fluctuations in intensity, making forecasts particularly difficult.

[20] Early on August 24, hurricane hunters struggled to find a circulation center as Danny neared the Lesser Antilles,[21] and the system weakened to a tropical depression by 12:00 UTC as it passed between Guadeloupe and Dominica.

The islands of Antigua, Anguilla, Barbuda, Montserrat, Nevis, Saba, St. Eustatius, and St. Kitts were placed under a tropical storm warning the following day.

[2] Leeward Islands Air Transport cancelled 40 flights across the eastern Caribbean due to the hurricane and cruise ships altered their courses.

[22][23] Although members of the Haiti Office of Civil Protection issued an official statement to residents saying Danny was not a threat to the country, they convened to discuss potential preparations and the status of emergency supplies.

[29] Just a few days after Danny, Tropical Storm Erika brought devastating floods to Dominica, killing 30 people and wrecking tremendous damage.