No Chg Log_MSC Environment Objectives

Mobile Surveillance Capabilities – Environmental Objectives

(MSCEO)

Secure Border Initiative

United States Customs and Border Patrol (CBP)

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Mobile Surveillance Capabilities – Environmental Objectives (MSCEO)

TABLE OF CONTENTS

1.0 Introduction

2.0 Environmental Capability Needs

3.0 Southern Sector Environmental Overview

3.1 San Diego Sector Environment

3.2 El Centro Sector Environment

3.3 Yuma Sector Environment

3.4 Tucson Sector Environment

3.5 El Paso Sector Environment

3.6 Marfa Sector Environment

3.7 Del Rio (McAllen) Sector Environment

3.8 Laredo Sector Environment

3.9 Rio Grande Valley Sector Environment

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1.0 Introduction

The following data provide a summary of the natural and operationally generated environments to which Mobile Surveillance Capabilities (MSC) project equipment will be exposed during operation, storage, transportation and handling.

2.0 Environmental Capability Needs

The environmental data are provided in a series of Tables, described further below. In addition to the environmental data, these Tables describe both desired and required capabilities.

These Tables use the term “Threshold Acceptable Capability,” to describe the lowest level of environmental robustness compatible with deployment and operations. The entries in the Tables provide details.

These Tables use the term “Nominal Desired Capability (Objective),” to describe the desired level of environmental robustness consistent with deployment and operations.

These Tables use the term “Goal,” to describe a level of environmental robustness that offers opportunities for enhanced operations.

Table 2-1, Naturally Occurring Operating Environment, describes the environment associated with operation in the CBP Southern Border Sectors, and also provides additional temperature and altitude data to encompass the entire contiguous United States (CONUS) comprised of 48 States plus Washington, DC. Offerors should take care to consider the combined effects of natural solar radiation (as detailed in the table) with ambient temperature.

Table 2-2, Stressing Naturally Occurring Operating Environment, describes additional environmental conditions generally associated with adverse weather, which lead to adjustments in operational capability expectations, as reflected in detail in the Table. For example, a higher level of wind is described in this table.

Table 2-3, Natural Survival Environment, describes naturally occurring environmental conditions that in their extreme may necessitate temporary cessation of normal operations an thus may lead to adjustments in operational capability expectations, as reflected in detail in the Table. For example, lightning as specified in this table.

Table 2-4, Operationally Generated Environment, describes conditions that result from transporting the equipment from site to site or operating related equipment such as Land Mobile Radio. These unique conditions lead to unique capability expectations, as reflected in detail in the Table.

Order of Precedence. In the event of conflict between the overview information of this Section 2, and the Tables of this Section 2, the Tables of Section 2 will take precedence.

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Table 2-1. Naturally Occurring Operating Environment

Condition Environment Southern Border

Sectors Contiguous US

(CONUS)

Threshold Acceptable Capability

Nominal Desired Capability (Objective) Goal Offeror Cross-Reference

Temperature, Ambient Operating

-12ºC to 51 ºC (10ºF to 124ºF)

-26ºC to 51 ºC (-15ºF to 124ºF)

Altitude, Operating -40 to 9,000 feet mean sea level

(MSL)

-282 to 14,505 feet

MSL

Solar Radiation, Operating

1120 W/m2 (0.72 W/in2) Caution: solar radiation may induce heating beyond ambient temperatures.

Ref. MIL-STD-810 Method 505.4 Ref. NASA-HDBK-1001 Section 4.4.2.

Relative Humidity, Operating

5% to 100% with condensation/rain.

Reference MIL-STD-810F Method 507.4

Sand and Dust, Operating

1.06 g/m3 @ 29 km/hr (18 mph).

Reference MIL-STD-810, Method 510.4

Salt Fog, Operating 5% by weight.

Reference MIL-STD-810, Method 509.4

Wind, Operating Surface winds up to an average of 24 km/hr (15 mph) with gusts velocities up to an additional 20% beyond this average wind velocity.

Wildlife, Operating

The equipment must offer protection from the foraging, nesting, movement, and other natural behaviors of wildlife including insects, birds, reptiles, rodents, and other mammals.

Supplier’s product must operate in all stated Southern Border operating environments in this Table.

Any degradation in performance below stated/claimed specification or “datasheet” performance that occurs at the extremes of any of the environmental ranges (individually or in combination) in this Table shall be temporary, as well as thoroughly characterized, documented, and reported to the customer and users via appropriate documentation and operator training.

Full performance must return, without operator intervention, when environmental conditions recede from their extremes.

Supplier’s product must operate in all stated Southern Border operating environments in this Table.

No degradation in performance below stated/claimed specification or “datasheet” performance will occur at the extremes of any of the environmental ranges in this Table, whether these extremes occur individually or in combination of several environmental extremes.

Supplier’s product must operate in all stated CONUS operating environments in this Table.

No degradation in performance below stated/claimed specification or “datasheet” performance will occur at the extremes of any of the environmental ranges in this Table, whether these extremes occur individually or in combination of several environmental extremes.

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Table 2-2. Stressing Naturally Occurring Operating Environment

Environment Condition Threshold Acceptable Capability

Nominal Desired Capability (Objective) Goal Offeror Cross-Reference

Rain, Operating

Up to 6 inches/hour and 60 inches/year and this shall be considered in the construction and deployment of equipment. .

Reference MIL-STD-810F Method 506.4 and climatological data of MIL-HDBK- 310 Sections 5.1.11, 5.2.5.10, 5.3.1.9, and 5.3.2.5.

Snow, Operating

For horizontal surfaces a snow load of 25 kg/m2 (5.12 lb/ft2) per 24-hour period (equivalent to a 10-inch snowfall) to a maximum of 50 kg/m2 (10.2 lb/ft2) in a 72-hour period, provided none of the snow is removed from the surface during that time, should be considered for implementation purposes. Inclined surfaces need to support only as much snow as can accumulate on the slope involved. Reference ASME/ANSI 7-95.

Ice, Operating

Consideration for system and exposed components is 0.25” ( 6mm) ice accumulation, of specific gravity ranging from 0.2 (soft rime) to 0.9 (glaze).

Reference MIL-STD-810F Method 521.2.

Freeze-Thaw Cycles, Operating

Natural freeze-thaw cycle effects can exert great stress on susceptible components of materiel. Reference MIL- HDBK-310 Section 5.1.22

Wind, Operating Surface winds up to 56 km/hr (35 mph) with gust velocities up to an additional 20% beyond mean wind velocity.

Supplier’s product must operate in all stated operating environments in this Table.

Any degradation in performance below stated/claimed specification or “datasheet” performance that occurs at the extremes of any of the environmental ranges in this Table (individually or in combination) shall be temporary, as well as thoroughly characterized, documented, and reported to the customer and users via appropriate documentation and operator training.

In some conditions (e.g., snow and ice) operator intervention (e.g., system reset, snow/ice removal, etc.) may be required to resume full operation when environmental conditions recede from their extremes.

Supplier’s product must operate in all stated operating environments in this Table.

Any degradation in performance below stated/claimed specification or “datasheet” performance that occurs at the extremes of any of the environmental ranges in this Table (individually or in combination) shall be temporary, as well as thoroughly characterized, documented, and reported to the customer and users via appropriate documentation and operator training.

Full performance must return without operator intervention when environmental conditions recede from their extremes.

Supplier’s product must operate in all stated operating environments in this Table.

No degradation in performance below stated/claimed specification or “datasheet” performance will occur at the extremes of any of the environmental ranges in this Table, whether these extremes occur individually or in combination of several environmental

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Table 2-3. Natural Survival Environment

Condition Environment Southern Border

Sectors Contiguous US

(CONUS)

Threshold Acceptable Capability

Nominal Desired Capability (Objective)

Goal Offeror Cross-Reference

Temperature, Survival -22 ºC to 55 ºC (-8 ºF to 132 ºF)

-40 ºC to 55 ºC (-40 ºF to 132 ºF)

Wind, Survival when Deployed

Winds up to 96 km/hr (60 mph) with gust velocities up to an additional 20% beyond this mean wind velocity.

Wind, Survival when Stowed

Winds up to 145 km/hr (90 mph). Ref. ANSI/TIA- 222G.

Survive exposure in Southern Border Sectors environment in a non-operating condition

Survive exposure in Southern Border Sectors environment in a non-operating condition, without need for manual adjustments afterward.

Survive exposure in CONUS environment in a non-operating condition, without need for manual adjustments or software-driven calibration afterward.

Lightning NFPA-780, FAA-STD-019, Reference MIL-STD-464A, Implementation per Best Commercial Practices

Implemented to recognized standard guidelines (examples provided)

Proven track record of all weather performance

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Table 2-4. Operationally Generated Environment

Environment Condition Threshold Acceptable Capability

Nominal Desired Capability (Objective)

Goal Offeror Cross-Reference

Altitude, Shipping/Survival Sea Level to 45,000 feet mean sea level (MSL) Survive exposure in non-operating condition

Survive exposure in non-operating condition, without need for manual adjustments afterward.

Survive exposure in non-operating condition, without need for manual adjustments or software-driven calibration afterward.

Electromagnetic Emissions

FCC Title 47 CFR §15, Class A (Industrial Equipment) Compliant

Compliant with adequate margin to remain compliant as components (e.g., EMI gaskets) age and if necessary replaced/maintained per a maintenance schedule.

MIL-STD-461 Compliant in addition to FCC Title 47 CFR §15, Class A

Electromagnetic Compatibility

Also equipment to be deployed with an approximately 100 W VHF Land Mobile Radio (LMR) Transmitter, with Antenna Mounted on Truck Roof.

Reference MIL-STD-461

Minimal disruption of system when LMR is transmitting.

Rare disruption of system when LMR is transmitting (such as only at operational environmental extremes).

No disruption of system when LMR is transmitting, including operational environment

Transportability, Vibration

Transportable on unpaved roads, paved roads, and highways, including Interstate Highways at full legal speed with wind loading.

MIL-STD-810F,

Procedure I Figure 514.5C-17

MIL-STD-810F,

Procedure I Figure 514.5C-1, -2, & -3

MIL-STD-810F,

Procedure III for Integrated Assemblies

Off-road Transportability Applicable to solutions provided with a wheeled or tracked trailer or vehicle.

Supplier to specify capability of offering. Capabilities in order of approximate increasing severity are:

• Churchill Hilly Secondary Road Course C.

• Perryman Cross Country Course 1,

• Perryman Cross Country Course 2.

• Churchill Hilly Area Course B, and

• Churchill Hilly Area Course A.

For course descriptions, please see DTIC Accession Number ADA103325. Title: Vehicle Test Facilities at Aberdeen Proving Ground, 06-July-1981. Publicly available at: http://handle.dtic.mil/100.2/ADA103325.

Offerors are encouraged to report on other equivalent test courses, if such courses have been or are planned to be used.

MIL-STD-810F,

Procedure I Figure 514.5C-17

Demonstrated Off-Road Capability

Formally Demonstrated Off-Road Capability on known test course. Ref.

MIL-STD-810F,

Procedure III for Integrated Assemblies http://handle.dtic.mil/100.2/ADA103325

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Environment Condition Threshold Acceptable Capability

Nominal Desired Capability (Objective)

Goal Offeror Cross-Reference

Transportability, Natural Hazards

Resistant to natural hazards present in travel, especially off-road travel, including vegetation such as tree limbs and brush, wildlife such as insects, birds, reptiles, rodents, and other mammals, and surface obstacles such as rocks, logs, and tree stumps.

Resistant

Highly Resistant including specific protective features such as brush guards and skid plates.

Same as Nominal Desired Capability (Objective)

3.0 Southern Sector Environmental Overview

This section is provided for informational purposes only to sensitize offerors to the environmental conditions and variations of the nine Southern Border Sectors. The geographic location of these nine Southern Border Sectors can be obtained at the following website http://www.cbp.gov/linkhandler/cgov/careers/customs_careers/border_careers/bp_agent/sectors_ map.ctt/Sectors_Map.pdf .

Order of Precedence. In the event of conflict between this Section 3 (including its subsections), and the Tables of Section 2, the Tables of Section 2 will take precedence.

3.1 San Diego Sector Environment

San Diego Sector boundaries encompass all of San Diego County, and parts of Orange and Riverside Counties. San Diego Sector's western corridor is one of the most densely populated areas in the United States, to include the cities of San Diego, Chula Vista, El Cajon, Escondido, Oceanside, Anaheim, and Temecula. The Sector's central corridor is comprised primarily of a blend of sparsely populated remote and rural wilderness areas. The eastern corridor is a blend of rural mountain and ranching enclaves with populations ranging from a few hundred up to several thousand.

Terrain features within this Sector include beaches, estuaries, coastal plains, steep canyons and ravines, high desert, and mountains over six thousand feet in elevation. There are numerous environmentally sensitive and protected areas in the Sector, including the Otay Mountain Wilderness and Tijuana Estuary. Dense, low laying brush and scrub trees cover much of the rural terrain throughout.

Weather conditions vary greatly throughout the Sector. The western corridor generally maintains year-round mild temperatures that average 50 to 80 degrees F. The central and eastern corridors can experience extremes in temperatures ranging from subfreezing to well over 100 degrees F.

San Diego experiences an average annual rainfall of 16 inches. Eastern portions of the Sector can experience occasional snowfall and high winds. In addition, the western portion of the Sector experiences frequent coastal eddies (a combination of low clouds and fog), which extend several miles inland.

Wildfires are a very real and persistent threat throughout the Sector. The fire season extends from May through November.

The combination of climatic extremes, rugged terrain, dense urban corridors, and protected environmental areas presents a complex challenge to conducting daily enforcement operations.

As such, the Border Patrol uses considerable ingenuity and flexibility in order to achieve its mission.

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3.2 El Centro Sector Environment

Terrain in the El Centro Sector area is largely comprised of rugged, inhospitable mountains, lush agricultural areas, and sandy, low-lying desert areas. Included in the area, are the Jacumba Wilderness area, Anza Borrego State Park, the Imperial Sand Dunes Recreation Area and several military reservations as well as large areas of desert that have been designated as critical habitat for threatened species. These areas all present special enforcement challenges because of the environmental and safety concerns that exist there.

The main population centers include the cities of El Centro and Calexico, with Mexicali to the south. Temperatures in the area may vary greatly between day and night. During the winter months, temperatures range from moderate to extreme cold during hours of darkness, especially in the mountains. During the summer, temperatures may exceed 120 degrees F during the day.

Daily high temperatures routinely exceed 100 degrees F from mid April through October.

The Imperial Valley receives only about 3 inches of annual rainfall, however, very little is needed to hinder border operations along the only slightly improved roadways used for patrol.

High winds can produce limited visibility lasting from a few minutes to several hours. Dense, early morning fog is common in the cooler months.

3.3 Yuma Sector Environment

The Yuma Sector is comprised of 76,000 square miles divided between California, Arizona and Nevada. The topography of the area is diverse consisting of rough sandy desert terrain, mountains and river valleys. There are several mountain ranges with elevations of over 4,000 feet.

The Yuma Sector's southern area of operation is primarily arid desert and includes 125 miles of linear border with Mexico. It includes the Great Sonoran Desert, the Imperial Sand Dunes, the Colorado and Gila Rivers and large agricultural areas. The main population centers include the cities of Yuma, Wellton, and San Luis.

Large portions of the Yuma Sector fall within the Cabeza Prieta National Wildlife Refuge, Luke Air Force Range, BMGR, and Yuma Proving Ground. The refuge and military ranges are highly sensitive areas, which require extensive high-level liaison and on-going coordination. Due to environmental issues and range safety concerns that must be adhered to and addressed, liaison and communication channels are open and continuous in order to support Border Patrol field operations as well as military training and environmental preservation.

Rains and flash flooding normally occur during the monsoon season in late summer and early fall. Rains vary in intensity from a light mist to downpours that create flash flood conditions.

During moderate to heavy rains and monsoon season, the ability to effectively patrol the immediate border area is greatly hindered by flooded, impassable roadways, which may affect operations for long periods of time.

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Beginning in late April, sustained daytime temperatures above 100 degrees F can be expected.

By mid-June, temperatures can reach the 120-degree F mark and are normally sustained through the month of August. High temperatures negatively affect operations due to reports of lost or distressed persons, and the necessity to conduct search and rescue operations.

High winds and sand storms are frequent and they can be unpredictable and range in duration from several minutes to several hours. They vary in intensity from minor blowing sand to near zero visibility conditions which can severely impact operations.

3.4 Tucson Sector Environment

The Tucson sector's southern area features valleys divided by mountain ranges aligned north and south. Much of the terrain is arid desert with native vegetation varying from low desert growth and grasslands to forests in the higher elevations. Agricultural areas are located in and around Casa Grande, Phoenix, Tucson, and Willcox.

Well-traveled trails traversing through canyon passes in rugged terrain are used regularly by Items of Interest . The rugged terrain poses significant problems for Border Patrol personnel attempting east-west travel in order to intercept smuggling operations.

West Desert Corridor begins south of Arivaca, AZ, east of the Tres Bellotas Gate and spans west to the Yuma County line. To the west of the Baboquivari Mountains lies the Tohono O'Odham Indian Nation. This terrain is primarily a flat land with small hills lining the Baboquivari Valley.

The majority of the West Desert Corridor is comprised of protected lands, military reservations, and the Tohono O'odham Indian Nation.

The town of Altar, Sonora, Mexico is about 60 miles to the south of the West Desert Corridor.

The majority of aliens entering on the West Desert Corridor travel through or stay in Altar.

The vastness of the area and the lack of cover for relief from the harsh elements make it a very dangerous crossing zone.

The Nogales Corridor is the most rugged of the three sector corridors. It consists of vast meadows, deep canyons, mountains, and ample washes, which flow north south. To the east of Nogales, AZ are the Patagonia Mountains and to the west are the Pajarito and Bartlett Mountains. The corridor encompasses the Sonoita and Nogales Stations AORs.

The eastern portion of the Naco/Douglas Corridor is adjacent to the New Mexico State line. The San Bernardino Valley is bordered on the east by the Guadalupe and Peloncillo Mountain ranges and to the west by the Chiricahua Mountains, within the Coronado National Forest. Elevations in these ranges reach 10,200 feet and pose a significant enforcement problem for Border Patrol personnel. Steep mountain slopes combined with dense vegetation and trees provide excellent cover and concealment for anyone attempting to evade Border Patrol personnel.

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The Sulphur Springs Valley is situated in the center of the Douglas Corridor. This valley is bordered on the east by the Chiricahua and Dos Cabezas Mountains and on the west by the Dragoon and Mule Mountains. Elevations in the Dragoons and Mule Mountains range from 7,900 to 8,800 feet

The San Pedro Valley lies in the western portion of the Douglas corridor. The Valley's eastern border is the Dragoon and Mule Mountain ranges. To the southwest are the Huachuca Mountains and to the west are the Whetstone Mountains. The Huachuca Mountains are adjacent to the Mexican border. Hereford and the city of Sierra Vista as well as Fort Huachuca are nestled in the Huachuca Mountain foothills.

3.5 El Paso Sector Environment

El Paso Sector encompasses 35 counties that extend approximately 500 miles into the interior from the border. The area covers approximately 125,000 square miles (121,000 in New Mexico;

4,500 in Texas). There are 109 miles of river frontage and 180 miles of land border adjacent to Mexico. The terrain in the area varies greatly.

Different stations patrol the 268 total miles of border. Lordsburg, Deming, and Santa Teresa Station patrol areas are arid New Mexico desert, with canyons, rocky hills and mountains. These areas are extremely isolated, with heavy brush in certain locations. Water is scarce through these areas, making it very difficult to traverse in hot weather. The large ranches and lack of landmarks make it easy to become lost. The Fabens and Fort Hancock Stations patrol the Rio Grande River in primarily agricultural areas of west Texas.

There are several large, swift-moving irrigation canals, as well as large expanses of isolated desert in the patrol areas of these stations. The Las Cruces and Alamogordo Stations patrol the interior of El Paso Sector. These areas have thick brush, and are bordered by mountainous regions of New Mexico. The Carlsbad, Truth or Consequences, and Albuquerque Stations also patrol the interior of the El Paso Sector. These areas vary from thick brush to open desert.

Large mountains with steep cliffs are scattered throughout New Mexico. The elevation of this region varies from 4,500 feet to over 12,000 feet, and the climate variances can be just as great.

The El Paso and Ysleta Stations operate in primarily urban areas of west Texas. There are several deep, swift-moving drainage canals that pose extreme drowning hazards, as well as other public safety hazards associated with an urban metropolitan environment. Generally, there is a three to five degree drop in temperature for every 1,000 foot rise in elevation.

The washes and playas (dry lakebeds) are susceptible to flash flooding during the July-October monsoon season. Extreme highs throughout the area are 112 degrees F with the extreme low reaching 22 degrees F.

3.6 Marfa Sector Environment

The Marfa Sector is unique in that it has such a wide spectrum of climate, ranging from sub-zero temperatures in the Amarillo Station region to almost sub-tropical temperatures in Presidio, For Official Use Only • Page 12 of 14 • Procurement Sensitive

Texas. The sector also features terrain that varies from dry sandy desert along the west side of the Plains area to cedar and oak covered hills along the extreme southeast section ( Lubbock Station). The Big Bend area, extending north through the Davis Mountains, is extremely rugged and elevations from six to eight thousand feet above sea level are not uncommon.

3.7 Del Rio (McAllen) Sector Environment

The terrain in the Del Rio Sector varies from rugged canyons and steep hills to rolling hills and flatland. The Rio Grande winds its way through deep canyons that give way to a large reservoir and river vegas covered in thick brush and tall, thick Carrizo cane. Vegetation in the rolling hills and wide open ranch land varies from low, sparse desert fauna to tall brush and trees capable of concealing foot movement.

Starting in the west, the Rio Grande travels through a remote deep river canyon with limited access from both sides of the river. The canyon consists of steep cliff walls on both sides of the river. The steep bluffs are broken, in a few locations, by canyons carved out over thousands of years by creeks and rivers that empty into the Rio Grande. The canyons branch into numerous smaller draws that blend in with the steep hills located near the river. Draws and canyons continue north of Highway 90 before the terrain becomes predominantly rolling hills. The ground in this area is rocky, making tracking a difficult task. Vegas, covered in heavy brush to 12 feet tall, exist at the base of the bluffs along the riverbanks on both sides of the river.

The Pecos River empties into the Rio Grande near Comstock, Texas. Its waters travel through a canyon that gets deeper as it nears the river. The river does not cover the entire width of the canyon as it did in the past, allowing ample room for moving along the river in the canyon.

Access to the canyon is limited and the canyon itself acts as a natural barrier to lateral movement, which causes most traffic to circumvent the canyon. Steep bluffs eventually taper off allowing river access at countless locations throughout the rest of Del Rio Sector. The bluffs on the Mexican side of the river often overlook the terrain on the U.S. side. Traffickers can access the high ground on the U.S. side without being observed. Steep banks give way to large expanses of flat farmland and rolling hills.

Several islands are present in the Rio Grande near Del Rio and downriver. The islands are generally covered in Carrizo cane and other vegetation. Along with islands, vegas with tall cane cover a majority of the terrain down river from the dam. Trails through the cane allow movement without being detected from a distance.

Del Rio Sector experiences mild winters and extreme heat in the summer. Normal daily summer temperatures generally range in the 90s F with highs up to 115 degrees F.

Average annual rainfall is 18.8 inches in Del Rio, with deviations of two inches or more in other parts of the Sector. Predominately, the heavier rains begin in the spring and carry into the fall months. The sector also experiences early morning ground fog that normally burns off quickly after sunrise.

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3.8 Laredo Sector Environment

The terrain in the southern part of Laredo Sector is generally characterized by gently rolling hills of south Texas brush near Laredo to steeper hills north of Laredo. Elevations range from 400 feet along the river to 900 feet in the north. Several deep arroyos, washouts and creeks provide drainage into the Rio Grande. Broad sections of flat area are located between rolling hills away from the river. Terrain along the river consists of two levels of riverbank. The water level bank extends from 5 to 200 meters from the river's edge. Beyond the water level bank a higher bank slopes at a 30-50% grade away from the river. Terrain on the Mexican side is similar.

The area in the northern part of Laredo Sector around the Dallas/Fort Worth area is mostly an urban environment containing over five million inhabitants. High-rise buildings and industrial parks are common throughout the area. The terrain outside of the metropolitan area is open and flat with dense wooded areas near east Texas. Temperatures throughout the Sector vary greatly ranging from below freezing in the winter to over 100 degrees F in the summer. Precipitation also varies considerably, ranging from less than 20 inches in the south to more that 50 inches annually along the Texas-Louisiana border.

3.9 Rio Grande Valley Sector Environment

The Rio Grande Valley Sector is adjacent to the Mexican state of Tamaulipas and the Mexican cities of Matamoros and Reynosa. This physical location accounts for many of the threat conditions found.

The Sector possesses a large coastal shoreline, a large population base, and a well-established infrastructure on both sides of its international border.

The Rio Grande Valley Sector's easternmost boundary is comprised entirely of Gulf of Mexico shoreline. This proximity to the Gulf of Mexico accounts for the mostly tropical weather conditions that are experienced year round and accounts for the Sector's susceptibility to natural phenomena such as hurricanes and or flood conditions.

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