Tropical Depression Nineteen-E was a weak yet costly tropical cyclone that caused significant flooding throughout Northwestern Mexico and several states within the United States in September 2018. The storm was also the first known tropical cyclone to form over the Gulf of California. Nineteen-E originated from a tropical wave that left the west coast of Africa on August 29 to 30. It continued westward, crossed over Central America, and entered the northeastern Pacific Ocean by September 7. It then meandered to the southwest of Mexico for the next several days as it interacted with a mid-to-upper level trough. The National Hurricane Center (NHC) continued to track the disturbance for the next several days as it traveled northward. A surface trough developed over the Baja California peninsula on September 18. Despite disorganization and having close proximity to land, the disturbance developed into a tropical depression in the Gulf of California on September 19, after having developed a circulation center and more concentrated convection. The system peaked with maximum sustained winds of 35 mph (55 km/h) and a minimum central pressure of 1002 mbar (29.59 inHg).
One day after forming, the depression quickly deteriorated and dissipated after making landfall in Sonora. Overall, the depression affected eleven Mexican states, with torrential rainfall and flooding ensuing in Baja California Sur, Sinaloa, and Sonora. Thirteen individuals were killed in Chihuahua, Sinaloa, and Sonora, and over $40 million (2018 USD) in agricultural losses were recorded. Excessive rainfall led to the inundation of at least 300,000 structures in Sinaloa. Total damage in Sonora and Sinaloa reached $224 million. Two children died in Sinaloa months after the storm as a result of unrepaired damage. 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. Damage estimates totaled about $250 million (USD) in the aforementioned states. Minor damage was also reported in New Mexico.
Meteorological history
Tropical Depression Nineteen-E's origins can be traced back to a tropical wave that departed from the west coast of Africa between August 29 and 30. On August 31, it generated Tropical Depression Six, which would later become Hurricane Florence. The wave continued to track westward at low latitudes, leaving Florence behind in the far eastern tropical Atlantic Ocean. The wave eventually moved over Central America and crossed into the far northeastern Pacific Ocean by September 7. The wave then slowed down and leisurely moved westward, south of Mexico for the next week or so. Meanwhile, a mid-level shortwave trough dropped southward from the United States, entering Mexico on September 9. 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. Around that time, the NHC noted the system had the potential for future tropical development. The low moved southwestward for the next several days. The trough and a plume of moisture rushed northward towards the Baja California peninsula just as the tropical wave was arriving. An area of low pressure formed several hundred miles south of the southern coast of Mexico on September 14 at 12:00 UTC. A surface trough with a north-to-south orientation developed over Baja California Sur on September 18 with thunderstorms having developed from the deep tropics to the Gulf of California.
The disturbance moved into the Gulf of California on September 19. A circulation center and more concentrated convection formed along the trough. Despite stronger wind shear and its proximity to land, the disturbance consolidated into a tropical depression around 12:00 UTC. The genesis of Nineteen-E was unexpected, having occurred after the NHC had downgraded the 5-day formation chance to low. 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. Six hours later, the depression's maximum sustained winds peaked at 35 mph (55 km/h). 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. At 00:00 UTC on September 20, the depression's minimum central pressure decreased to 1002 mbar (29.59 inHg). Around 03:00 UTC, Nineteen-E made landfall between the cities of Ciudad Obregón and Guaymas in Sonora. After moving ashore, the rugged terrain of Sonora quickly weakened the depression. Six hours after landfall, the NHC noted that the depression's convection had taken on a more linear look and that it had lost its closed surface circulation. The NHC reported that Nineteen-E dissipated around 12:00 UTC that day. Nineteen-E's remnants continued to travel northward, while causing severe flooding in Mexico. After entering the United States, the remnants tracked eastward and drew in moisture from the Gulf of Mexico, causing flash flooding in several states.
Impact
Mexico
Tropical Depression Nineteen-E caused flooding throughout northwestern Mexico. In total, at least eleven Mexican states were affected by the depression, with Baja California Sur, Sonora, and Sinaloa being impacted the hardest. Torrential rainfall affected the Baja California peninsula for a few days before genesis occurred on September 19 through the system's dissipation. The National Meteorological Service of Mexico reported that Baja California Sur received heavy rainfall, with totals of approximately
3–4 in (70–100 mm) and an isolated value of up to 4.88 in (124 mm) being reported in the southern portion of the state. 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. On September 19, in anticipation of hazardous effects from Nineteen-E, a green alert was issued off-shore of Mexico.
On September 20, the depression made landfall in Sonora, Mexico. The torrential rains associated with the depression were the most intense to impact the state in the last decade. According to Conagua, the National Water Commission, over 8 in (200 mm) of rain fell in a 10-hour period in some locations. While most of the rainfall in Sonora came from Nineteen-E, sporadic bursts of convection unaffiliated with the depression contributed additional rainfall. At least 13 municipalities in Sinaloa received heavy rainfall, with a total of 5.5 in (140 mm) being recorded at El Cazanate. In the municipality of Nogales, more than 300 tonnes of mud, stones, and garbage were removed from roads in order to make them passable for vehicles. Additionally, two bodies were recovered by Nogales police after having been dragged across the border, into Arizona, by strong currents. Over 100 people were rescued from floods and the total number affected is estimated to be in the hundreds of thousands. Traffic on Federal Highway 15 in southern Sonora was interrupted as strong water currents flowed across the road. Authorities used social media to alert the public to stay off the highway. Additionally, 30 people were rescued from a passenger bus that had gotten stuck between streams. The National Center for Disaster Prevention reported that total damage in Sonora was 1.03 billion pesos (US$54.6 million).
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. One person was killed in the community of Goritos where 14.150 in (359.41 mm) of rain fell. In Culiacán, a total of six deaths occurred. One person drowned after heavy rainfall occurred. Additionally, three women were swept away by floodwaters from the El Piojo stream; two bodies were later recovered. Two indirect deaths occurred from electrocution. Classes at all levels of education were cancelled in several municipalities as a result of the flooding. Many roads were damaged, with sinkholes appearing on Federal Highway 15. A bridge collapsed in Ahome, forcing the closure of a road. More than 16,000 people were evacuated and 13 shelters were set up due to severe flooding. Following the deluge of rainfall, the Culiacán River Derivative Dam overflowed. The Eustaquio Buelna dam filled to more than 144 percent of its capacity. A freight train derailed while traveling from Retes Station to Techa in Mocorito. The Cahuinahua canal overflowed in the municipality of El Fuerte, flooding several communities. Damage to agriculture exceeded 800 million pesos (US$41 million) in Sinaloa after 14,000 hectares (35,000 acres) of agricultural fields and hydro-agricultural infrastructure were inundated. In total, over 500,000 birds and 15,000 heads of cattle, goats, and pigs were killed and swept away by the currents of engorged rivers. As a result, approximately 58,000 jobs were impacted. Over 300,000 structures were inundated in Sinaloa, including 160 schools; in the coastal city of Los Mochis, 70,000 buildings were damaged. The National Center for Disaster Prevention reported that total damage in Sinaloa was 3.18 billion pesos (US$169 million). At least 804 million pesos (US$42.7 million) in losses occurred in the economic sector and 755 million pesos (US$40.1 million) in losses occurred in the communications and transportation sector. Around 48.4 percent of the total was damage and losses in education, health, housing, hydraulic systems, and sports and cultural attractions. Over 2.2 million pesos (US$117,000) in damage and losses occurred to public infrastructure.
In the state of Chihuahua, three people were reported dead. A 51-year-old man and a 45-year-old woman drowned in the municipality of Satevó after being dragged by strong currents. In Namiquipa, the body of a 45-year-old man was recovered after he drowned while attempting to cross an engorged stream. Rainfall in the southwestern portion of the state was 2.0–3.9 in (50–99 mm), with a small region reporting up to 7.83 in (199 mm). In Guanajuato, heavy rainfall forced the reopening of floodgates at the Ignacio Allende Dam.
United States
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. In those states, damage estimates totaled about $250 million (USD). Minimal damage was also reported in the state of New Mexico.
In Arizona, Nineteen-E caused flash flooding at multiple locations on September 19. 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. In Thatcher, 1.5–2.5 in (38–63 mm) of rain fell, causing two homes to flood. Additionally, multiple roads flooded after a drainage canal overflowed. Several dorm rooms at Eastern Arizona College flooded, along with several apartments in the area. Near Silverbell, 3 ft (0.9 m) of water ran over the intersection of two roads. Near Vicksburg, severe rain caused flash flooding, resulting in road closures near Interstate 10. It was also reported that 1.56 in (39.6 mm) of rain fell in Tucson, where a person walking near the Pantano Wash was rescued after being overcome by rising waters. 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. Damage was reported at approximately $1,000 (USD). The National Weather Service stated that no other damage had been reported for New Mexico. In Albuquerque a peak rainfall total of 1.40 in (35.6 mm) was reported.
In Texas, Nineteen-E brought torrential rains that caused significant flooding in many areas. In Everman, a suburb of Fort Worth, water was reportedly up to 6 ft (2 m) deep in places. Over 60 homes were inundated, which forced many people to evacuate. On September 23, the body of a 23-year-old was recovered from a creek in Fort Worth. 14 people had to be rescued from broken-down cars in the Dallas-Fort Worth area. Near Austin, 61 people from a wedding venue had to be rescued by firefighters. Additionally, the Shady River RV Resort off of State Highway 29 and near Interstate 35 was evacuated. In Arlington, a 23-year-old man drowned after being swept off a bridge. At Dallas/Fort Worth International Airport, over 8 in (200 mm) of rain fell. In Dallas, 15 people, including five police officers, were rescued from rising waters. Additionally, in Killeen, 34 patients were evacuated from the Metroplex Hospital after a lightning strike knocked out power to the facility. Several roads in Nolan, Jones, Tom Green, Uvalde, Rockwall, Fannin, Sutton, and Schleicher Counties were closed due to flooding and damage. Near Farmersville, high water along a railway bridge led to a train derailment. While no one was injured, numerous freight train cars went off the rails. In Electra, water up to 1 ft (0.3 m) deep was flowing over multiple city streets. In Knox City, a vehicle stalled after its driver attempted to drive through flood waters. Additionally, Sonora was hit with a 25 ft (7.6 m) wall of water after the spillways to several dams were activated. Water flooded all access points to the town, preventing first responders from entering. Over 250 homes in the village were either damaged or destroyed by the flood waters.