The Sierra Madre Oriental () is a mountain range located 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 form the western "backbone" of North America, Central America, South America, and Antarctica.
Setting
Spanning the Sierra Madre Oriental runs from the Rio Grande on the border between Coahuila and Texas south through Nuevo León, southwest Tamaulipas, San Luis Potosí, Querétaro, and Hidalgo to northern Puebla, where it joins with the east-west running Eje Volcánico Transversal of central Mexico. The northernmost are the Sierra del Burro and the Sierra del Carmen which reach the border with the United States at the Rio Grande. North of the Rio Grande, the range continues northwestward into Texas and beyond as the Davis and Guadalupe Ranges.
thumb|Sierra Madre Oriental in [[San Pedro Garza Garcia, Nuevo Leon.]]
Mexico's Gulf Coastal Plain lies to the east of the range, between the mountains and the Gulf of Mexico coast. The Mexican Plateau, which averages in elevation, lies between the Sierra Madre Oriental and the Sierra Madre Occidental further west.
The climate of the Sierra Madre Oriental is drier than the rainforest areas further south. The Serranias del Burro in the northern range is much drier, semi-arid to arid, yet annually orographically induces and/or intensifies notably vigorous thunderstorm activity in April and May. This small region consistently is a particularly active area for supercells with significantly severe hail and tornadoes, which first form over to just leeward of the mountains then move eastward, sometimes hundreds of kilometres (miles) past the Rio Grande River into Texas.
thumb|left|250px|The Sierra Madre Oriental in Hidalgo state.
Highest major summits
Cerro El Potosí, at above sea level (ASL), is the highest point of the Sierra Madre Oriental and the state of Nuevo León
{| class="wikitable sortable"
|+The Highest Major Mountain Peaks of Sierra Madre Oriental
!Rank
!Mountain Peak
!State
!Mountain Range
!Elevation
!Prominence
!Isolation
|-
|align=center|1
|Cerro el Potosí PB
|
|Sierra Madre Oriental
|align=center|3,721 m<br/>12,208 feet
|align=center|1,876 m<br/>6,155 feet
|align=center|570 km<br/>354 miles
|-
|align=center|2
|Cerro San Rafael PB
|
|Sierra Madre Oriental
|align=center|3,712 m<br/>12,178 feet
|align=center|1,395 m<br/>4,577 feet
|align=center|628 km<br/>390 miles
|-
|align=center|3
|Sierra de la Marta PB
|<br/>
|Sierra Madre Oriental
|align=center|3,700 m<br/>12,139 feet
|align=center|1,010 m<br/>3,314 feet
|align=center|607 km<br/>377 miles
|-
|}
Ecology
This long range of tall mountains is noted for its abundant biodiversity and large number of endemic species of plants and wildlife, from the dry north to the wetter south. The Sierra Madre Oriental pine-oak forests are found at high elevations in the range ( above sea level). To the east, the Tamaulipan matorral occupies the range's lower slopes in Nuevo León and northern Tamaulipas, while the Veracruz moist forests cover the lower slopes of the central range, and the eastern slopes at the southern end of the range are home to the Veracruz montane forests. West of the range, the Mexican Plateau is home to deserts and xeric shrublands, including the Chihuahuan Desert to the north, the Meseta Central matorral on the central part of the plateau, and the Central Mexican matorral on the southern plateau.
Much of the wildlife can also be found in the Sierra Madre Occidental, which runs parallel to these mountains along western Mexico.
<gallery mode="packed" heights="120px">
File:El Cielo Biosphere Reserve, Municipality of Gómez Farías, Tamaulipas, Mexico (16 April 2001).jpg|Road into the cloud forest of El Cielo Biosphere Reserve, Municipality of Gómez Farías, Tamaulipas, Mexico (16 April 2001)
File:Sierra Madre Oriental, Municipality of Miquihuana, Tamaulipas, Mexico (10 August 2003).jpg|Gravel road through the arid interior slopes of the Sierra Madre Oriental, Municipality of Miquihuana, Tamaulipas, Mexico (10 August 2003)
File:Sierra Peña Navada, Municipality of Miquihuana, Tamaulipas, Mexico (10 August 2003).jpg|Looking down on the Marcela valley from Sierra Peña Navada, Municipality of Miquihuana, Tamaulipas, Mexico (10 August 2003)
</gallery>
Flora
Pine-oak forests are dominated by several species of pine, such as Pinus nelsonii, P. cembroides, P. pseudostrobus, and P. arizonica, and oak, such as Quercus castanea and Q. affinis. The canopy of moist forests is dominated by trees up to in height, including Brosimum alicastrum, Manilkara zapota, Celtis monoica, Bursera simaruba, Dendropanax arboreus, and Sideroxylon capiri.
Fauna
Birds of the forest include the Mexican chickadee, Montezuma quail, Strickland's woodpecker, zone-tailed hawk and several species of jay.
Pine-oak forests in Coahuila are part of the migration route of monarch butterflies (Danaus plexippus).
See also
- Mountain peaks of Mexico
- Sierra Madre Occidental