On September 21, Hilary was declared as a Category 1 hurricane, while located close to the Mexican coastline, where the storm brought heavy rainfall and flooding.

Beginning to enter cooler Ocean temperatures, Hilary began to weaken by September 25 but briefly restrengthened into a Category 4 the following day.

[2] The following day, the area of disturbed weather began to become better organized, and the National Hurricane Center (NHC) upgraded its chances of tropical cyclone development to the "Medium" category.

Several hours later, after sustaining no deep convection atop its center, Hilary was declared a remnant low, located several hundred miles away from any landmasses.

Over the next 3 days, Hilary's remnant low subsequently moved towards the southwest, before dissipating after 1200 UTC on October 3, about 1,050 mi (1,690 km) to the west of the southern tip of Baja California.

[1] The NHC noted the possibility of up to 10 in (250 mm) of rain in the high-terrain of Guerrero and Oaxaca, and large swells were expected to impact coastal areas.

[12] A red emergency alert was additionally in place for the region; officials urged residents to be prepared to evacuate, and tourists were advised to stay indoors.

[citation needed] Due to rough surf, small craft advisories were put in effect, and swimmers were advised to take extreme caution.