EF0 tornado, (Bro)Brownsville Arp, Texas, July 26, 2020

1. EF065 to 85 mphthis tornado

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF0

Date

July 26, 2020

Touchdown

3:32 AM CDT (08:32 UTC)

Lifted

3:36 AM CDT (08:36 UTC)

On the ground

4 minutes

Path length

3.4 miles (5.5 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$250,000

County

Cameron County

Touchdown point

25.873, -97.429

Lift-off point

25.922, -97.436

Record number

2007260232-01

23 damage points were recorded along this path by NWS BRO, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 104 mph.

• Nine windows blown out with some curtain wall failure. Wind speed capped at 75 mph based on limited nearby damage to trees or other structures.
• This was the only section damaged. Aircraft (737) was moved into the hanger with no damage to the aircraft. Actual speed lowered to 75 mph.
• Single window blown out of hangar building.
• Unanchored old jet stairs flipped. Center of gravity was low to the ground. Lower wind speed used but not as low as if structure was very llight,. .

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

Hurricane Hanna, the 2020 Atlantic season's first Hurricane, made landfall along the unpopulated Padre Island National Seashore on the mid-Kenedy County coastline as a Category 1 storm at around 5 PM Central Time Saturday, July 25th, carrying sustained 90 mph winds with gusts over 100 mph in a small portion of the inner eye wall. The hurricane spun slowly but steadily into southern Kenedy and northern Hidalgo County through just after midnight on the 26th, then through Starr County as a Tropical Storm before moving into Tamaulipas before daybreak and eventually near Monterrey, Nuevo Leon, by noon before dissipating during the evening of the 26th. Following the passage of the inner eye wall, broad feeder bands of torrential rains and gusty tropical storm force winds continued through the mid to late morning hours of July 26th, slowly migrating from east to west across the populated Rio Grande Valley. ||Other than storm surge flooding, which peaked just north of Baffin Bay on the Kleberg and Nueces County coast near Corpus Christi, Hanna's memory for the Rio Grande Valley will be flooding rainfall, power outages, and an array of damage to poorly constructed buildings, from minor roof damage to complete demolition. Between 8 and 15 inches of rain fell from Port Mansfield to Harlingen, and along Interstate Highway 2 out through Mission and Sullivan City. The combination of high rainfall, locally high rainfall rates, and poor drainage left between 18 inches and four feet of water depth in many areas, most commonly from western Cameron through southeastern Hidalgo County, as well as a separate pocket in the Mission/La Joya/Sullivan City area. The rainfall wiped out 95% of the region's cotton crop; the combination of crop loss and production loss was more than one third of a billion dollars alone ($366 million)...most of which was in the Rio Grande Valley region. ||At the peak of the storm, 250 thousand electric customers were without power, including all of Willacy County. Though storm surge was cut short by strong westerly flow across Cameron County, radiating swells did produce a notable surge of 3 feet or greater (estimated) from near Port Mansfield through Kenedy County. When the damage and economic loss is counted to infrastructure and agriculture combined, it is likely that Hanna cost at least one billion dollars across the Rio Grande Valley and the Deep S. Texas ranch country.

Hurricane Hanna made landfall along the Kenedy county|coast on the evening of July 25, 2020. As Hanna pushed inland, its|eastern outer rain bands produced several areas of rotation. One|area of stronger rotation developed south of Brownsville just across|the Rio Grande in Mexico. The Brownsville radar briefly detected|a debris signature as it moved northward toward the Brownsville|airport. The Brownsville airport, in addition to residents in|nearby neighborhoods, reported wind damage.||The initial touchdown was discovered about 2.3 miles south |of Brownsville/South Padre Island International Airport. Here, an|empty tractor trailer was moved on an angle into a stand of trees, |an unanchored travel trailer was flipped, a storage shed was flattened,|and several mesquite trees lost large limbs. A few minutes later, several |areas of damage occurred on the west side of the Brownsville airport. |A dozen windows were blown out of an airplane hangar building, an|unanchored old jet staircase was flipped and a garage door|collapsed inward. In addition, a Boeing 737 aircraft was moved into a|hangar, causing damage to the hangar wall. No damage was noted to|the plane itself. As the tornado moved to the north northwest,|several large tree limbs were snapped, in addition to a weak|uprooted tree. Finally further north, two homes lost large sections|of their roofs with most walls still standing. The brief tornado|then lifted with no other tornado damage found.||Based on the survey and quality of construction materials surveyed, the tornado was rated EF0 with peak winds of 75 mph.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

5 minutes of warning. NWS BRO issued a tornado warning for this county at 08:27 UTC, 5 minutes before the tornado touched down, in force until 09:00 UTC.

The county was under a tornado watch, issued at 04:07 UTC and running to 12:51 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 05:28 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Brownsville International (BRO), 2 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Brownsville radar (KBRO), 2 km away, was scanning. The volume nearest the touchdown began at 08:32 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2020 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

2 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.