The rugged terrain disrupted the cyclone's structure; Gert entered the Pacific Ocean as a depression near the state of Nayarit on September 21, where it briefly redeveloped a few strong thunderstorms before dissipating at sea five days later.

Combined with saturated soil following Tropical Storm Bret's passage a month earlier, the rain triggered widespread floods and mudslides that isolated thousands of people across numerous communities.

Gert's winds were at their strongest upon landfall in Mexico, yet the worst effects in the country were also due to freshwater flooding after an extreme rainfall event in the Huasteca region resulted in water accumulations as high as 31.41 inches (798 mm).

An increasing number of major rivers burst their banks over a period of several days, fully submerging extensive areas of land around the Pánuco basin.

In Gert's wake, the road networks across the affected countries remained severely disrupted for extended periods of time, hampering rescue missions and relief efforts in badly flooded regions.

The wave tracked westward across the tropical Atlantic at a rapid pace and relatively low latitudes, where its interaction with the Intertropical Convergence Zone fostered the formation of convection.

Although most of the cloud field brushed over the northern coast of South America, the system survived its contact with land and emerged over the southwestern Caribbean Sea on September 13.

Given these structural changes alongside a defined surface circulation, forecasters at the National Hurricane Center (NHC) classified the system as a tropical depression at 1800 UTC on September 14, when it was located 105 miles (169 km) north of the Atlantic coast of Panama.

While the storm's center remained land-bound for nearly two days, parts of its large circulation abutted the adjacent Caribbean and Pacific waters to draw in moisture and heat.

Its duration over water—and with that any opportunity for additional strengthening—was curtailed by a mid- to upper-level trough over the eastern Gulf of Mexico; it turned the storm to the north-northwest and brought it over the coast of Belize the next day.

[7] After crossing the Yucatán Peninsula and winding down over land,[8] Gert entered the Bay of Campeche offshore Champotón as a tropical depression late on September 18.

[4][15] While Gert was still located over the peninsula, the government of Mexico issued a tropical storm watch for the Gulf Coast from the city of Veracruz northward to Soto la Marina, Tamaulipas.

After hours of prolonged rainfall, many Pacific regions such as Quepos, Pérez Zeledón, and Osa experienced flooding and landslides, which inflicted moderate damage to roads and bridges.

[20] High winds brought great destruction to about 65 percent of the vegetation in the Manuel Antonio National Park, vastly impacting the tourism-driven economy of Quepos.

[24] Sustained winds from the storm reached no more than 40 mph (64 km/h) upon landfall near Bluefields,[4] though they downed trees and power lines and generated high waves of up to 12 feet (3.7 m) offshore.

Gert produced significant coastal flooding on moving ashore near Bluefields and Tasbapauni, prompting about 1,000 residents and hundreds of indigenous Miskito villagers to evacuate.

[25] Farther inland, prolonged heavy rain caused numerous rivers to overflow, which led to disastrous freshwater flooding, especially in departments around Lake Nicaragua.

[31] The impact on the ecology was profound: rivers, estuaries, and mangroves in and around lakes Nicaragua and Managua, as well as the inhabiting fauna, suffered from severe erosion and siltation.

[34] Damaging floods swept through 13 of the country's 18 departments; however, northern Honduras and the Mosquitia Region, which had already endured the onslaught of Tropical Storm Bret in the previous month, bore the brunt of the devastation.

[26] The Río Grande de San Miguel caused an excessive discharge of water just southwest of Usulután,[39] washing out about 2,500 acres (10 km2) of crops from adjacent plantations.

[7] The effects of the storm were limited to localized floods, however, which cut off one road to traffic and forced the inhabitants from low-lying areas in Chetumal and Felipe Carrillo Puerto to evacuate to higher ground.

[44] Upon Gert's final landfall, high gales and waves battered wide stretches of coastline in the states of Tamaulipas and Veracruz, though hurricane-force winds were largely confined to areas within the cyclone's southern eyewall.

Despite the severity of the winds, the worst of Gert was due to orographic lift when its broad circulation interacted with the eastern side of the Sierra Madre Oriental, generating extreme precipitation over much of the Huasteca region.

[12][34] The first signs of damage were from high winds on September 20, which uprooted trees and tore off residential roofs in Tuxpan, Naranjos, Cerro Azul, and Poza Rica.

[46] Following Gert's extreme rains, catastrophic flooding struck Mexico's Huasteca region over a period of several days, as many of its rivers rose to critical levels.

[50] Roughly 2,000,000 acres (8,100 km2) of land around the Pánuco basin and Tampico were under water, including vast amounts of citrus, coffee, corn, maiz, bean, grain, and soy crops.

[19] Emergency crews were dispatched to assess the damage and distribute life supplies to the affected population, including 90,940 pounds (41,250 kg) of food, 1,422 mattresses, and 1,350 blankets.

Although most storm victims received aid within a few days, the deteriorated road network caused a large delay in relief efforts to the hard-hit Mosquitia region.

[49] In the wake of Gert, the amount of respiratory disease and skin infection cases rose slightly, although the overall health situation for the country remained well under control.

By two weeks after the hurricane, over 65,000 people across the region had been accommodated in shelters; most stayed there until the floods receded, although many who returned home a month later continued to rely on relief provisions.