Tropical Storm Fernand was a short-lived

tropical cyclone A tropical cyclone is a rapidly rotating storm system with a low-pressure area, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depending on its locat ...

that caused severe flooding in northern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

in early September 2019. The sixth named storm of the

2019 Atlantic hurricane season The 2019 Atlantic hurricane season was the fourth consecutive above-average and damaging season dating back to 2016. The season featured eighteen named storms, however, many storms were weak and short-lived, especially towards the end of the ...

, Fernand developed from a broad area of low pressure that was first monitored in the southeastern

Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...

on August 31. Gradual organization ensued as the low moved westward, and it developed into a tropical depression early on September 3. The cyclone quickly strengthened into Tropical Storm Fernand six hours after formation, and attained peak winds of early on September 4. However, easterly

wind shear Wind shear (; also written windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical ...

and the cyclone's close proximity to the Mexican coast prevented further development, and Fernand weakened slightly before making

landfall Landfall is the event of a storm moving over land after being over water. More broadly, and in relation to human travel, it refers to 'the first land that is reached or seen at the end of a journey across the sea or through the air, or the fact ...

along the coast of northeastern Mexico at 15:15 UTC September 4. Fernand quickly weakened to a tropical depression as it moved over the

Sierra Madre Oriental The Sierra Madre Oriental () is a mountain range in northeastern Mexico. The Sierra Madre Oriental is part of the American Cordillera, a chain of mountain ranges (cordillera) that consists of an almost continuous sequence of mountain ranges that ...

, and by 03:00 UTC on September 5, the cyclone had dissipated over the rugged terrain of Mexico. Fernand caused torrential, much-needed rainfall in

Monterrey Monterrey (, , abbreviated as MtY) is the capital and largest city of the northeastern Mexican state of Nuevo León. It is the ninth-largest city and the second largest metropolitan area, after Greater Mexico City. Located at the foothills of th ...

and other communities.

Meteorological history

Early on August 31, 2019, the

National Hurricane Center The National Hurricane Center (NHC) is the division of the United States' NOAA/National Weather Service responsible for tracking and predicting tropical weather systems between the IERS Reference Meridian, Prime Meridian and the 140th meridian ...

(NHC) began monitoring a broad area of low pressure located over the southeastern

for

tropical cyclogenesis Tropical cyclogenesis is the development and strengthening of a tropical cyclone in the atmosphere. The mechanisms through which tropics, tropical cyclogenesis occur are distinctly different from those through which temperate cyclogenesis occu ...

. Slow, but steady development occurred as the low moved generally westward across the southern Gulf of Mexico. On September 2, shower and thunderstorm activity associated with the low became more concentrated, and the surface circulation became better defined. Although the disturbance still lacked a well-defined center by the following morning, the continued trend of organization and the system's threat to northeastern Mexico resulted in the issuance of advisories on Potential Tropical Cyclone Seven at 09:00 UTC September 3. Shortly thereafter, first-light visible satellite images indicated the presence of a well-defined center of circulation, signifying the formation of a tropical depression at 15:00 UTC. The cyclone continued to become better organized, and scatterometer data from 16:00 UTC that day revealed an area of tropical storm-force winds to the west of the center. Based on this data, the NHC upgraded the depression to Tropical Storm Fernand at 18:00 UTC on September 3. Fernand continued to quickly strengthen as it moved westward, and by 03:00 UTC on September 4, it attained its peak intensity with maximum sustained winds of , as evidenced by an

NOAA The National Oceanic and Atmospheric Administration (NOAA ) is an American scientific and regulatory agency charged with forecasting weather, monitoring oceanic and atmospheric conditions, charting the seas, conducting deep-sea exploratio ...

Hurricane hunter Hurricane hunters, typhoon hunters, or cyclone hunters are aircrews that fly into tropical cyclones to gather weather data. In the United States, the organizations that fly these missions are the United States Air Force Reserve's 53rd Weather ...

aircraft investigating the system. Although the cyclone was forecast to strengthen further before reaching the Mexican coast, the effects of moderate easterly to southeasterly wind shear and the entrainment of dry air into the storm's circulation prevented further intensification. By mid-day on September 4, much of the associated convection had moved inland over Mexico, and Fernand weakened slightly before making landfall on the northeastern coast of Mexico at around 15:15 UTC about north of

La Pesca La Pesca is a small town in the Mexican state of Tamaulipas. It is located on the Gulf of Mexico, at the mouth of the Río Soto La Marina, between the Laguna Madre to the north and the Laguna Morales to the south. It stands due east of state cap ...

with maximum sustained winds of . Just hours after moving inland, the surface circulation of Fernand quickly became poorly defined, and the cyclone weakened to a tropical depression at 21:00 UTC on September 4. Weakening continued as Fernand moved further inland, and at 03:00 UTC on September 5, the cyclone dissipated over the very rugged terrain of the

Preparations and impact

Mexico

Upon the initiation of advisories on Potential Tropical Cyclone Seven early on September 3, the

Government of Mexico The Federal government of Mexico (alternately known as the Government of the Republic or ' or ') is the national government of the Mexico, United Mexican States, the central government established by its constitution to share sovereignty over the ...

issued a tropical storm warning for

northward to Barra El Mezquital in northeastern Mexico. The warning was extended northward to the mouth of the

Rio Grande The Rio Grande ( or ) in the United States or the Río Bravo (del Norte) in Mexico (), also known as Tó Ba'áadi in Navajo language, Navajo, is one of the principal rivers (along with the Colorado River) in the Southwestern United States a ...

river and southward to Barra del Tordo at 18:00 UTC with the designation of Tropical Storm Fernand. In preparation for the storm, the Mexican government activated

Plan DN-III-E The Plan DN-III-E or Civil Relief and Aid Plan for Disasters (Spanish: ''Plan de Auxilio a la Población Civil en Casos de Desastre'') is a series of measures implemented primarily by the Mexican Ministry of National Defense, specifically the Mexic ...

, sending 4,000 troops to the northeastern states to assist in disaster relief. Fernand produced torrential rainfall across much of northeastern Mexico, including the states of

Coahuila Coahuila, formally Coahuila de Zaragoza, officially the Free and Sovereign State of Coahuila de Zaragoza, is one of the 31 states of Mexico. The largest city and State Capital is the city of Saltillo; the second largest is Torreón and the thi ...

Nuevo León Nuevo León, officially the Free and Sovereign State of Nuevo León, is a Administrative divisions of Mexico, state in northeastern Mexico. The state borders the Mexican states of Tamaulipas, Coahuila, Zacatecas, and San Luis Potosí, San Luis ...

Tamaulipas Tamaulipas, officially the Free and Sovereign State of Tamaulipas, is a state in Mexico; one of the 31 states which, along with Mexico City, comprise the 32 federal entities of Mexico. It is divided into 43 municipalities. It is located in nor ...

and

San Luis Potosí San Luis Potosí, officially the Free and Sovereign State of San Luis Potosí, is one of the 32 states which compose the Federal Entities of Mexico. It is divided in 59 municipalities and is named after its capital city, San Luis Potosí. It ...

. In some parts of Nuevo León, six months-worth of rain fell within just six hours, causing rivers and streams to overflow their banks as floodwaters inundated roads, bridges, homes and, buildings. Schools and public transportation lines across the state were closed on September 5, and over 400 schools sustained damages as a result of effects from the storm. In the municipality of García, a Venezuelan man died after he was swept away by floodwaters while trying to clean a sewer; two others who were with him at the time were rescued. In

, a taxi driver was forced to abandon his vehicle after it sank in rapidly-rising floodwaters. A man in Monterrey who was carried away by floodwaters along the Santa Catarina river was rescued by Civil Protection workers, and sustained no major injuries, while another man and his dog who attempted to drive through floodwaters in

La Huasteca La Huasteca is a geographical and cultural region located partially along the Gulf of Mexico and including parts of the states of Tamaulipas, Veracruz, Puebla, Hidalgo, San Luis Potosí, Querétaro and Guanajuato. It is roughly defined as the ar ...

also required rescue after being caught in the strong current of the floodwaters. On September 7, Governor of Nuevo León

Jaime Rodríguez Calderón Jaime Heliodoro Rodríguez Calderón (born 28 December 1957), sometimes referred to by his nickname "''El Bronco''", is a Mexican politician. He served as the Governor of Nuevo León from 2015 to 2021 and was a candidate in the 2018 presidentia ...

declared a state of emergency for Nuevo León, further announcing that he would request funding and resources from the National Disaster Fund to aid in repairs and relief efforts. Initial damage in Nuevo León was estimated to be Mex$7.5 billion (US$383 million). Two months later, the National Civil Protection found that the damage in Nuevo León was just Mex$222 million (US$11.3 million), much less than the initial estimation. The government confirmed the total damage to be Mex$861 million (US$43.7 million).

United States

Although the center of Fernand remained over northeastern Mexico, the storm's outer rainbands brought much-needed rainfall to portions of drought-stricken

South Texas South Texas is a geographic and cultural region of the U.S. state of Texas that lies roughly south of—and includes—San Antonio. The southern and western boundary is the Rio Grande, and to the east it is the Gulf of Mexico. The population of th ...

. Rainfall totals of or more were reported in several locations in the state, peaking at in Port Isabel. Cameron County public beach access No. 5 and 6, as well as

Boca Chica Beach Boca Chica is an area on the eastern portion of a subdelta peninsula of Cameron County, at the far south of the US state of Texas along the Gulf Coast. It is bordered by the Brownsville Ship Channel to the north, the Rio Grande and Mexico to the ...

were temporarily closed on September 3 due to high tides and the risk of rip currents produced by the storm. Scattered storms were seen across the Corpus Christi area in the outer bands.

References

External links