EF1 tornado, Allen to Fairview, Texas, April 10, 2008

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

April 10, 2008

Touchdown

4:04 AM CDT (09:04 UTC)

Lifted

4:10 AM CDT (09:10 UTC)

On the ground

6 minutes

Path length

7.2 miles (11.5 km)

Path width

175 yards (160 m)

Deaths

0

Injuries

0

Property damage

$12 million

County

Collin County

Touchdown point

33.086, -96.737

Lift-off point

33.157, -96.646

Record number

0804100304-01

Several rounds of storms moved across north Texas on April 8th through 10th. Numerous reports of large hail were received on Tuesday evening. A lone supercell evolved during the afternoon hours of the 9th, producing tornadoes and large hail along its path. Later that evening and into Thursday morning a squall line tracked across north Texas, producing damaging winds and tornadoes into the morning hours.

A damage survey conducted by the National Weather Service in Fort Worth found that a tornado touched down in southwest Allen and traveled northeast seven miles to south McKinney. Structural damage occurred to approximately 50 homes in Allen with several of them sustaining roof damage. A total of 300 residences reported some type of damage including downed trees and fences. In McKinney...numerous homes either lost part or all of their roofs or sustained roof damage due to impacts from flying debris. The Collin County Regional Airport sustained damage to several hangars and some aircraft. Throughout both towns, numerous power lines and poles were downed. Estimated insured losses for both cities is $10 million. This tornado was rated an EF-1 with winds speeds around 90-95 MPH.

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

25 minutes of warning. NWS FWD issued a tornado warning for this county at 08:39 UTC, 25 minutes before the tornado touched down, in force until 09:15 UTC.

The county was under a tornado watch, issued at 03:40 UTC and running to 10:42 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 General Thunderstorms Risk. The outlook in force was issued at 06:01 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.

The Dallas/Ft Worth radar (KFWS), 84 km away, was scanning. The volume nearest the touchdown began at 09:02 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 2008 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

32 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.