EF1 tornado, (Mfe)Miller Intl Arp, Texas, June 30, 2011

1. EF065 to 85 mph

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

2. EF186 to 110 mphthis tornado

   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

EF1

Date

June 30, 2011

Touchdown

5:57 PM CDT (22:57 UTC)

Lifted

6:04 PM CDT (23:04 UTC)

On the ground

7 minutes

Path length

0.4 miles (0.6 km)

Path width

30 yards (27 m)

Deaths

0

Injuries

1

Property damage

$500,000

County

Hidalgo County

Touchdown point

26.118, -98.194

Lift-off point

26.120, -98.200

Record number

1106301657-01

7 damage points were recorded along this path by NWS BRO, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 86 mph.

• Touchdown location. Fences damaged, trampolines overturned and a few shingles mentioned. Narrow damage path.
• Looking east-southeast toward subdivision.
• View of touchdown point, looking toward the east-southeast. Minor roof damage (mostly shingle) was noted here. Crack also seen in interior ceiling of house.
• Loss of roofing material to a wood frame structure being used as an office building. Rafters were toenailed to the frame, but hurricane straps were not attached. Structural damage visible inside.

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

A series of convergent feeder bands associated with Tropical Storm Arlene, which made landfall nearly 300 miles south of the area along the northern State of Veracruz coast, dropped welcome tropical rains on the Lower Rio Grande Valley during the morning and early afternoon of June 30th, putting a definite dent into the water year (since October 1, 2010) drought in Cameron, Willacy, and eastern Hidalgo County. Overall, between 1 and 4 inches fell in the region. Much of the rain was moderate, though heavier bands created pockets of urban flooding in Cameron County. ||A small but potent thunderstorm developed during the evening in very unstable air left behind by the outer bands, in extreme southern Hidalgo County. Low level wind direction and speed shear were sufficient to create a rotating cell, which developed a quick but damaging tornado around 6 PM CDT.

This short-lived tornado touched down in a subdivision approximately 4 miles east-northeast of the city of Hidalgo in southern Hidalgo County. Most of the damage in this area was limited to the overturning of trampolines, the knocking down of wooden privacy fences, an outdoor storage building, and minor shingle damage to the roof of two homes. A (relatively empty) moving truck was also blown on its side in the subdivision. The tornado strengthened as it approached an import/export business on the west side of US-281. Here, an office building lost between 25% and 33% of the roof as the tornado continued moving westward. Much of the roofing material landed on a car parked behind the office building, resulting in the injury of the driver. In this area, a single-wide mobile home was heavily damaged, as well as a couple of semi trucks. Before lifting, tornadic winds knocked down several hundred feet of concrete block fencing. No damage was seen beyond this point by the National Weather Service survey crew or officials from the city of Pharr.

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

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

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 General Thunderstorms Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:52 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.

Mcallen/Miller International (MFE), 8 km from the path, in the two hours either side.

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

The Brownsville radar (KBRO), 81 km away, was scanning. The volume nearest the touchdown began at 22:58 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 2011 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

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.