Tornadoes · United States · Alabama · 2015
EF1 tornado, Sulphur Spgs, Alabama, April 3, 2015
This EF1 tornado ran 2.3 miles across DeKalb County on April 3, 2015, touching down at 9:05 PM CDT and reaching 75 yards wide. It killed nobody.
The rating scale
Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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.
The record
- Rating
- EF1
- Date
- April 3, 2015
- Touchdown
- 9:05 PM CDT (02:05 UTC)
- Lifted
- 9:08 PM CDT (02:08 UTC)
- On the ground
- 3 minutes
- Path length
- 2.3 miles (3.7 km)
- Path width
- 75 yards (69 m)
- Deaths
- 0
- Injuries
- 0
- County
- DeKalb County
- Touchdown point
- 34.744, -85.619
- Lift-off point
- 34.745, -85.578
- Record number
- 1504032005-01
The damage survey
24 damage points were recorded along this path by NWS HUN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 105 mph.
- 5832 Alabama highway 75 flat rock or idler Alabama
Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.
What the Weather Service recorded
A cold front intersecting a warm and unstable environment led to a broken band of thunderstorms during the late afternoon and evening hours, some of which were supercellular in nature. These storms moved east-southeast at 35-45 mph and exited northern Alabama between 930 and 10 pm CDT. One tornado was confirmed in DeKalb County with a few narrow swaths of wind damage reported in other portions of north Alabama.
A tornado touched down in the Ider community of eastern DeKalb County, Alabama. The tornado first touched down along County Road 783. Numerous hardwood trees were snapped and uprooted. A small outbuilding was damaged near the intersection of County road 776. The tornado then tracked just north of County Road 776 before intersecting County Road 788. ||Damage to trees was fairly widespread in this area. Several homes or buildings also received minor roof or structural damage. The tornado reached its maximum intensity just west of Alabama Highway 75. One home there sustained significant roof damage with the majority of the roof removed. An anchored outbuilding was destroyed and several over homes sustained minor damage. Also, a power pole was snapped off and many large hardwood trees were snapped about 20 feet above the ground. ||The tornado then crossed Alabama Highway 75, snapping and uprooting trees along both sides of the road. The tornado began to weaken as it moved east-southeast, crossing County Road 372. Very minor roof damage was noted to a home and a few trees were uprooted. The tornado then dissipated on the east side of County Road 791 in the Cartersville, Alabama community after uprooting a few trees on the eastern slopes of Sand Mountain.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
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 severe thunderstorm watch, issued at 23:50 UTC and running to 03:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 23:50 UTC | 03:00 UTC | Severe Thunderstorm Watch | HUN |
| 01:52 UTC | 02:15 UTC | Severe Thunderstorm Warning | HUN |
| 01:54 UTC | 02:30 UTC | Severe Thunderstorm Warning | HUN |
| 02:10 UTC | 02:21 UTC | Tornado Warning | HUN |
| 02:26 UTC | 03:00 UTC | Severe Thunderstorm Warning | HUN |
| 02:32 UTC | 03:00 UTC | Tornado Warning | HUN |
| 02:43 UTC | 02:55 UTC | Tornado Warning | HUN |
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 forecast that day
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 00:38 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 air that afternoon
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.
Nashville Metro, TN (KBNA), 00:00Z
2.1 hours before the tornado, 179 km from the path. April 4, 2015.
- Mixed-layer CAPE
- 2 J/kg
- Mixed-layer CIN
- -133 J/kg
- Surface CAPE
- 32 J/kg
- Mixed-layer LCL
- 593 m above ground
- 0-6 km bulk shear
- 65 kt
- 0-1 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 16 m²/s²
- 0-3 km storm-relative helicity
- 107 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 5.2 K/km
Nashville Metro, TN (KBNA), 12:00Z
9.9 hours after it, 179 km from the path. April 4, 2015.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -91775 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 983 m above ground
- 0-6 km bulk shear
- 90 kt
- 0-1 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- -152 m²/s²
- 0-3 km storm-relative helicity
- -99 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 3.1 K/km
The radar
The Northeast Alabama radar (KHTX), 49 km away, was scanning. The volume nearest the touchdown began at 02:05 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.
What was reported nearby
Local storm reports within 60 km of the path, in the three hours either side.
| Time (UTC) | Report | Where | County | Remark |
|---|---|---|---|---|
| 02:03 UTC | TSTM WND DMG | 2 N Ider | Dekalb, AL | MANY TREES DOWN ON HIGHWAY 75, ABOUT 2 MILES NORTH OF IDER, CROSSING BETWEEN CARTERSVILLE AND IDER. POSSIBLE TORNADO. |
| 02:24 UTC | TSTM WND DMG | 2 N Ider | Dekalb, AL | DAMAGE TO A HOME AND GARAGE IN THE CARTERSVILLE AREA OUTSIDE OF IDER ALONG HWY 75. POSSIBLE TORNADO. |
| 02:24 UTC | TSTM WND DMG | Fyffe | Dekalb, AL | MULTIPLE TREES DOWN IN THE FYFFE AREA. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2015 tornado in AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are
The other tornadoes of April 3, 2015
4 more were confirmed in the United States that day.
What this means
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.
Sources
NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.