EF3 tornado, Grant to Stamp, Alabama, April 10, 2009

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 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 mphthis tornado

   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

EF3

Date

April 10, 2009

Touchdown

3:02 PM CDT (20:02 UTC)

Lifted

3:35 PM CDT (20:35 UTC)

On the ground

33 minutes

Path length

32.5 miles (52.3 km)

Path width

440 yards (402 m)

Deaths

0

Injuries

5

Counties

Marshall, Jackson and DeKalb counties

Touchdown point

34.495, -86.249

Lift-off point

34.556, -85.775

Record number

0904101402-02

A strong upper level storm moving across the Mississipi Valley brought a dry line and cold front into north Alabama during the afternoon and early evening hours. Several classic supercell thunderstorms developed by early afternoon in northwest Alabama, sweeping across the remainder of north Alabama during mid to late afternoon hours. Many of the storms produced very large hail, up to baseball and softball sized, producing significant damage, especially from Decatur through Madison and northwest Huntsville. One of the supercells produced a long track tornado producing damage of up to EF-3 intensity which struck northeastern Marshall County, crossed Lake Guntersville, and moved into southern DeKalb County.

A tornado touched down approximately 2.5 miles south southeast of Grant along Campbell Mill Road. A few houses sustained minor roof damage on the southeast side of Grant. At least two mobile homes sustained major damage from falling trees. The tornado continued east crossing Old Union Road, Columbus City Road, and Cardessa Lane before descending into the Tennessee River Valley. The tornado crossed Highway 79 at approximately 307 PM CDT at the Baker Mountain Road intersection. At this point the damage path width was just below a half of a mile wide. One woman was injured when a tree fell on her car near the Waterfront Grocery store. Several houses sustained substantial damage on the east side of Highway 79 and many trees were snapped and uprooted. The roof was blown off of one home and a brick wall collapsed. The tornado crossed a small inlet onto the south side of Preston Island, wiping out several boat docks and boat houses. Several homes sustained significant damage on the island from falling trees. At least two wood homes had complete roof collapse and partial wall collapse.||The tornado crossed Lake Guntersville into the South Sauty community. At least one person was injured in this area when he was caught outside during the tornado. At this point, the damage path width increased to at least a half a mile wide. Several well built homes were damaged by falling trees along Memonminee Road. At least 20 boat houses were destroyed in the community. Along Chilcotin Road a well constructed two story brick house lost its roof. Also falling trees damaged several camper trailers. One trailer was blown into Lake Guntersville. Thousands of trees were uprooted or snapped along the path of the tornado in Marshall county. The tornado crossed the CR 67 causeway and very shortly after moved into Jackson county. On CR 67, tornadic winds damaged the shoulder of the roadway as it crossed.

Just east of CR 67, this tornado continued east northeast from Marshall county and into southern Jackson county. Several homes were destroyed in the Macedonia community along with numerous large trees uprooted and snapped. Three TVA high voltage powerline towers also collapsed. As the tornado approached Powell, a double wide manufactured home was shifted off its foundation with total roof collapse and complete destruction to the front of the home.

This destructive tornado continued to move east northeast from Jackson county into Dekalb county. Just on the east side of Highway 35, a large metal industrial building that was securely anchored into the ground was completely destroyed. In Sylvania, significant damage occurred to several homes in the Stonebrook division. One home was completely lifted off its foundation and driven nearly 4 feet into the ground. Sporadic damage continued just to the east of Sylvania until the tornado apparently lifted between 335 and 340 PM CDT, just south of the Mahan Crossroads community in west central Dekalb county.

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. One was issued for the county at another hour that day.

The county was under a tornado watch, issued at 16:33 UTC and running to 22:03 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 High Risk, with a 0.30 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 18:45 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.

Fort_payne (4A9), 27 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), 46 km away, was scanning. The volume nearest the touchdown began at 20:02 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 2009 tornado in AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are

63 more were confirmed in the United States that day.

All 64 of them

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.