Overall, the depression affected eleven Mexican states, with torrential rainfall and flooding ensuing in Baja California Sur, Sinaloa, and Sonora.

Remnant moisture from Nineteen-E led to severe flooding within the U.S. states of Arizona, Texas, Oklahoma, and Arkansas and the death of one person.

The trough continued to track southward for the next few days and a low- to mid-level low developed just south of the southern tip of the Baja California peninsula on September 12.

An area of low pressure formed several hundred miles south of the southern coast of Mexico on September 14 at 12:00 UTC.

The NHC stated that Nineteen-E was the first tropical cyclone to have formed over the Gulf of California based on records dating back to 1949.

[1] Around that time, the NHC noted that banding features had become slightly more defined and an area of strong convection was present in the eastern semicircle.

In total, at least eleven Mexican states were affected by the depression, with Baja California Sur, Sonora, and Sinaloa being impacted the hardest.

[10] Torrential rainfall affected the Baja California peninsula for a few days before genesis occurred on September 19 through the system's dissipation.

[9] The cyclone's quick formation over the Gulf of California, which was attributed to warmer-than-normal sea surface temperatures, left insufficient time for warnings to be issued for municipalities.

[20] In Sinaloa, record-breaking rainfall of 98 US gal (370 L) per 11 sq ft (1 m2) was reported in Culiacán, exceeding the amount the state had received from Hurricane Manuel in 2013.

[33] The National Center for Disaster Prevention reported that total flood damage in Sinaloa was over 3.182 billion pesos ($165.8 million USD).

[20] Tropical Depression Nineteen-E's remnant moisture also caused flooding in the U.S. states of Arizona, Texas, Oklahoma, and Arkansas after drawing strength from the Gulf of Mexico.

Approximately 2–3 in (50–80 mm) of rain fell near Sahuarita, causing washes of up to 2 ft (0.6 m) that left several individuals stranded in their vehicles.

[42] It was also reported that 1.56 in (39.6 mm) of rain fell in Tucson,[39] where a person walking near the Pantano Wash was rescued after being overcome by rising waters.

[40] In New Mexico, it was reported that a large cottonwood tree blew down near the Kirtland Air Force Base after winds of 50 knots (58 mph; 93 km/h) occurred.

[48] Several roads in Nolan,[49] Jones,[50] Tom Green,[51] Uvalde, Rockwall, Fannin,[46] Sutton, and Schleicher Counties were closed due to flooding and damage.

[8] In Pontotoc County, four water rescues were conducted and a state of emergency was declared as rainfall and flooding associated with Nineteen-E made many roads near the city of Ada impossible to navigate.

[61] In Mexico, severe flooding in Sonora and Sinaloa prompted the execution of numerous disaster plans and safety measures.

[62] On September 27, the municipalities of Ahome, Culiacán, Angostura, Badiraguato, Choix, Guasave, El Fuerte, Mocorito, Sinaloa, Salvador Alvarado, and Navolato were all declared disaster areas by the Government of Mexico.

[11] Moreover, the Mexican Army initiated the DN-3 plan for natural disasters and deployed some 2,000 soldiers in Sinaloa and Sonora to aid in relief efforts.

[64][62] In Sinaloa, four aircraft were sent to assist in cleanup efforts, three search and rescue teams were deployed, and two helicopters were used to transport supplies to flood victims.

[64] The governor of Sinaloa, Quirino Ordaz Coppel, encouraged citizens to contribute food, water, and clothing in order to assist with the relief effort.

[23] Several days later, the National Fund for Natural Disasters (Fonden) was activated to assist local and regional governments in responding to the flooding.

[65] Additionally, the Macrosimulacro 2018, a nationwide disaster evacuation drill,[66] was suspended as a precautionary measure in Sonora and Baja California Sur.

[68] The administrative coordinator for Sedesol, Carlos Castro Olivas, was arrested on October 18, 2018, and charged with the crimes of illegal negotiations to the detriment of public service and society and embezzlement in connection with the distribution of rotten mattresses following Nineteen-E.[69] Carlos Castro Olivas was acquitted on December 17, 2020, as a result of a lack of evidence after two key witnesses for the prosecution failed to appear in court.

[75] President Andrés Manuel López Obrador approved a request in February 2019 to improve hydraulic flood-prevention systems in the municipalities of Culiacán and Ahome.

[79] The National Commission for Aquaculture and Fisheries provided funds for the dredging of a dock and two water channels in the Santa María Bay, Angostura, Sinaloa, to alleviate the effects of Nineteen-E on the environment.

[80] In the United States, severe flooding in Texas resulted in both local and federal efforts being established in order to provide aid to victims.

On September 28, Governor Greg Abbott issued a disaster declaration for Ellis, Sutton, Tarrant,[81] Fannin, and Uvalde Counties in response to widespread and severe property damage caused by the floods.

[88] In Tarrant County, it was reported that various relief organizations were attempting to help with cleanup and recovery efforts within the Fort Worth suburb of Everman.