EF0 tornado, Trinity, Alabama, June 19, 2007

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

June 19, 2007

Touchdown

1:00 PM CDT (18:00 UTC)

Lifted

1:01 PM CDT (18:01 UTC)

On the ground

1 minutes

Path length

0.3 miles (0.4 km)

Path width

25 yards (23 m)

Deaths

0

Injuries

0

County

Morgan County

Touchdown point

34.589, -87.095

Lift-off point

34.590, -87.092

Record number

0706191200-01

An upper level circulation or disturbance known in meteorology as a Mesoscale-Convective-Vorticity center tracked eastward through the central Tennessee Valley during the morning hours. A moist an unstable airmass enabled rapid low-topped shower development by late morning as this system tracked through the area. A brief weak tornado was sighted in Trinity. This was in close proximity to the upper level circulation mentioned above. As this shower entered Madison, AL further to the east, a NWS employee observed thunder being heard, likely from a cloud to cloud lightning flash. Otherwise, no other cloud to ground lightning was noted, making this tornado an interesting phenomenon for further study. The University of Alabama-Huntsville ARMOR dual-polarization radar located at the Huntsville International Airport was in close proximity to this tornado and identified a couple of small low-level circulations within a band these showers, one in the vicinity of the tornado.

Representatives from the National Weather Service and Morgan County Emergency Management completed a survey of damage in the city of Trinity, AL. The survey found evidence of an EF-0 tornado on the Enhanced Fujita scale, with highest winds of 65 mph. The damage was confined mostly to uprooted trees and snapped limbs. One residence sustained some damage, mainly to sheds and fencing at the back of the property.

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. The outlook in force was issued at 16:29 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.

Decatur/Pryor Field (DCU), 15 km from the path, in the two hours either side.

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

The Northeast Alabama radar (KHTX), 100 km away, was scanning. The volume nearest the touchdown began at 17:58 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 2007 tornado in AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are

6 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.