Tornadoes · United States · Louisiana · 2021
EF1 tornado, Saint Tammany Parish, Louisiana, August 29, 2021
This EF1 tornado ran 4.9 miles across Saint Tammany Parish on August 29, 2021, touching down at 6:33 PM CDT and reaching 175 yards wide. It killed nobody, and did $25,000 of property damage.
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
- August 29, 2021
- Touchdown
- 6:33 PM CDT (23:33 UTC)
- Lifted
- 6:38 PM CDT (23:38 UTC)
- On the ground
- 5 minutes
- Path length
- 4.9 miles (7.9 km)
- Path width
- 175 yards (160 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $25,000
- County
- Saint Tammany Parish
- Touchdown point
- 30.211, -89.773
- Lift-off point
- 30.230, -89.853
- Record number
- 2108291733-01
The damage survey
33 damage points were recorded along this path by NWS LIX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 88 mph.
- Partial collapse of roof and roofing material.
- Metal roof off of a house on Lakeview Drive.
- Partial roof material missing from house. Time estimated from radar.
- some roof material missing on two houses. Time estimated from radar.
Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.
The warnings
8 minutes of warning. NWS LIX issued a tornado warning for this county at 23:25 UTC, 8 minutes before the tornado touched down, in force until 00:00 UTC.
The county was under a tornado watch, issued at 11:11 UTC and running to 23:50 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 11:11 UTC | 23:50 UTC | Tornado Watch | LIX |
| 12:00 UTC | 21:38 UTC | Flash Flood Watch | LIX |
| 12:00 UTC | 07:47 UTC | Flood Watch | LIX |
| 23:09 UTC | 07:30 UTC | Flash Flood Warning | LIX |
| 23:21 UTC | 15:45 UTC | Flash Flood Warning | LIX |
| 23:25 UTC | 00:00 UTC | Tornado Warning | LIX |
| 23:50 UTC | 10:54 UTC | Tornado Watch | LIX |
| 23:54 UTC | 00:30 UTC | Tornado Warning | LIX |
| 01:22 UTC | 02:00 UTC | Tornado Warning | LIX |
| 01:49 UTC | 15:08 UTC | Flood Warning | LIX |
| 04:50 UTC | 08:00 UTC | Flash Flood Warning | LIX |
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 19:50 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.
Slidell Radar S, LA (KSIL), 12:00Z
11.6 hours before the tornado, 11 km from the path. August 29, 2021.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -89790 J/kg
- Surface CAPE
- 543 J/kg
- Mixed-layer LCL
- 3256 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- -55 m²/s²
- 0-3 km storm-relative helicity
- 85 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.3
- 0-3 km lapse rate
- 4.3 K/km
Slidell Radar S, LA (KSIL), 00:00Z
0.4 hours after it, 11 km from the path. August 30, 2021.
- Mixed-layer CAPE
- 25 J/kg
- Mixed-layer CIN
- -2 J/kg
- Surface CAPE
- 65 J/kg
- Mixed-layer LCL
- 679 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km bulk shear
- 6 kt
- 0-1 km storm-relative helicity
- 36 m²/s²
- 0-3 km storm-relative helicity
- 73 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 5.0 K/km
The surface observations
Slidell (ASD), 14 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 21:35 UTC | 110° 20 kt | 29 | 1003 | +RA BR | ||
| 21:40 UTC | 100° 22 kt | 40 | 1003 | +RA BR | ||
| 21:42 UTC | 78 | 74 | 90° 21 kt | 40 | 1002.7 | +RA BR |
| 21:45 UTC | 90° 18 kt | 27 | 1002.7 | +RA BR | ||
| 21:50 UTC | 90° 18 kt | 31 | 1002.4 | +RA BR | ||
| 21:50 UTC | 77 | 73.4 | 100° 19 kt | 33 | 1002.4 | +RA BR |
| 21:53 UTC | 77 | 74 | 90° 23 kt | 41 | 1002.4 | +RA BR |
| 21:55 UTC | 100° 21 kt | 28 | 1002.4 | RA BR | ||
| 22:00 UTC | 90° 17 kt | 27 | 1002 | RA BR | ||
| 22:01 UTC | 77 | 74 | 90° 17 kt | 41 | 1002.4 | +RA BR |
| 22:05 UTC | 100° 15 kt | 22 | 1002.4 | +RA BR | ||
| 22:10 UTC | 110° 16 kt | 24 | 1002.4 | +RA BR | ||
| 22:12 UTC | 77 | 74 | 100° 20 kt | 40 | 1002 | +RA BR |
| 22:15 UTC | 100° 24 kt | 31 | 1002 | +RA BR | ||
| 22:20 UTC | 110° 22 kt | 33 | 1002 | +RA BR | ||
| 22:25 UTC | 100° 20 kt | 27 | 1002 | +RA BR | ||
| 22:30 UTC | 100° 17 kt | 30 | 1001.7 | +RA BR | ||
| 22:35 UTC | 90° 22 kt | 30 | 1001.4 | +RA BR | ||
| 22:40 UTC | 90° 21 kt | 1001.4 | +RA BR | |||
| 22:45 UTC | 120° 22 kt | 32 | 1001.7 | +RA BR | ||
| 22:50 UTC | 120° 24 kt | 1002 | +RA BR | |||
| 22:53 UTC | 78 | 74 | 110° 25 kt | 51 | 1001.7 | +RA BR |
| 22:55 UTC | 110° 19 kt | 31 | 1001 | +RA BR | ||
| 23:00 UTC | 90° 19 kt | 36 | 1001 | +RA BR | ||
| 23:05 UTC | 110° 22 kt | 34 | 1000.7 | +RA BR | ||
| 23:10 UTC | 110° 22 kt | 33 | 1000.7 | +RA BR | ||
| 23:15 UTC | 100° 20 kt | 34 | 1000.3 | +RA BR | ||
| 23:20 UTC | 100° 18 kt | 1000.3 | +RA BR | |||
| 23:21 UTC | 78 | 75 | 110° 18 kt | 37 | 1000.3 | +RA BR |
| 23:25 UTC | 100° 24 kt | 30 | 1000.3 | +RA BR | ||
| 23:30 UTC | 100° 19 kt | 28 | 1000 | +RA BR | ||
| 23:35 UTC | 110° 18 kt | 1000.3 | +RA BR | |||
| 23:40 UTC | 110° 26 kt | 40 | 1000.3 | +RA BR | ||
| 23:45 UTC | 100° 29 kt | 37 | 1000 | +RA BR | ||
| 23:49 UTC | 77 | 73.4 | 110° 26 kt | 46 | 1000 | +RA BR |
| 23:50 UTC | 100° 27 kt | 47 | 1000.3 | +RA BR | ||
| 23:53 UTC | 77 | 74 | 110° 24 kt | 49 | 1000.3 | +RA BR |
| 23:55 UTC | 100° 22 kt | 28 | 1000.3 | +RA BR | ||
| 00:00 UTC | 77 | 74 | 100° 22 kt | 39 | 1000 | +RA BR |
| 00:00 UTC | 100° 22 kt | 31 | 1000 | +RA BR | ||
| 00:04 UTC | 77 | 75 | 120° 23 kt | 43 | 1000 | +RA BR |
| 00:05 UTC | 120° 21 kt | 35 | 1000 | +RA BR | ||
| 00:07 UTC | 77 | 75 | 110° 21 kt | 43 | 1000 | +RA BR |
| 00:10 UTC | 22 kt | 37 | 1000 | +RA BR | ||
| 00:15 UTC | 27 kt | 43 | 1000 | +RA BR | ||
| 00:20 UTC | 100° 23 kt | 37 | 999.7 | RA BR | ||
| 00:25 UTC | 20 kt | 38 | 999.7 | +RA BR | ||
| 00:30 UTC | 30 kt | 45 | 999.3 | +RA BR | ||
| 00:32 UTC | 77 | 75 | 110° 25 kt | 47 | 999.7 | +RA BR |
| 00:35 UTC | 28 kt | 41 | 999.3 | +RA BR | ||
| 00:40 UTC | 110° 24 kt | 37 | 999.3 | +RA BR | ||
| 00:45 UTC | 120° 28 kt | 37 | 999.3 | +RA BR | ||
| 00:50 UTC | 110° 28 kt | 39 | 998.6 | +RA BR | ||
| 00:53 UTC | 77 | 75 | 110° 28 kt | 55 | 998.6 | +RA BR |
| 00:55 UTC | 110° 23 kt | 38 | 999 | +RA BR | ||
| 01:00 UTC | 110° 23 kt | 32 | 999.3 | +RA BR | ||
| 01:05 UTC | 110° 28 kt | 33 | 999 | +RA BR | ||
| 01:10 UTC | 120° 30 kt | 999 | +RA BR | |||
| 01:15 UTC | 110° 23 kt | 43 | 999.3 | +RA BR | ||
| 01:20 UTC | 120° 37 kt | 56 | 999.7 | +RA BR | ||
| 01:25 UTC | 120° 29 kt | 44 | 999.7 | +RA BR | ||
| 01:30 UTC | 120° 29 kt | 46 | 999.7 | +RA BR |
From the Iowa Environmental Mesonet's archive of airport observations.
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 |
|---|---|---|---|---|
| 22:10 UTC | HURRICANE | 5 Sse East New Orleans | St. Bernard, LA | WEATHERFLOW OBSERVATION AT BAYOU BEINVENUE SUSTAINED WINDS OF 82 MPH WITH GUST UP TO 99.;. |
| 22:11 UTC | TROPICAL STORM | 2 Nw Kenner | Jefferson, LA | NEW ORLEANS INTERNATIONAL AIRPORT (KMSY) SUSTAINED WINDS 62 MPH WITH GUSTS TO 81 MPH. |
| 22:16 UTC | TROPICAL STORM | 6 Wsw East New Orleans | Gmz530, LA | LAKEFRONT AIRPORT (KNEW) SUSTAINED WINDS OF 66 MPH WITH GUSTS UP TO 86 MPH. |
| 22:30 UTC | TROPICAL STORM | 4 Ne Laplace | Gmz530, LA | FRENIER LANDING SUSTAINED 62 MPH GUST 84 MPH. |
| 22:51 UTC | TROPICAL STORM | 1 Ne Waggaman | Jefferson, LA | JEFFERSON PARISH WEATHERFLOW OBSERVATION RECORDED SUSTAINED WINDS OF 53 MPH AND A GUST TO 82 MPH. |
| 23:01 UTC | TROPICAL STORM | 1 Ssw Mandeville | Gmz530, LA | WEATHERFLOW OBSERVATION AT MANDEVILLE SUSTAINED WINDS 37 MPH WITH A PEAK GUST OF 75 MPH. |
| 23:02 UTC | TROPICAL STORM | 12 Ssw Mandeville | Gmz530, LA | WEATHERFLOW OBSERVATION AT MID LAKE ON THE CASUEWAY NOW SUSTAINED 64 MPG GUST TO 86 MPH. |
| 23:33 UTC | TORNADO | 2 Se Eden Isle | St. Tammany, LA | A TORNADO TOUCHED DOWN IN EDEN ISLE JUST EAST OF I-10. THE FIRST SIGN OF VISIBLE DAMAGE WAS TO A VACANT CONDOMINIUM COMPLEX ON LAKE SHORE BLVD EAST. THE ROOF TO TWO OF THE BUILDINGS WERE PARTIALLY TORN WITH CONSTRUCTION |
| 01:37 UTC | HIGH SUST WINDS 62 | 1 Nnw Kenner | Jefferson, LA | ASOS STATION KMSY NEW ORLEANS INTL-LOUIS ARMSTRONG. WIND SPEEDS OF 62 MPH. GUSTS TO 90 MPH AT NEW ORLEANS INTERNATIONAL AIRPORT. |
| 01:56 UTC | TORNADO | 1 Sse Eden Isle | St. Tammany, LA | A BRIEF TORNADO TOUCHED DOWN IN EDEN ISLE ON MARINA DR WHERE SEVERAL HOUSES SUSTAINED ROOF AND FENCE DAMAGE. UPROOTED TREES AND ADDITIONAL PROPERTY DAMAGE WERE CAPTURED BY NOAA AERIAL IMAGERY IN THE TORNADO S PATH ALONG |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2021 tornado in LouisianaEvery tornado in Louisiana since 1950Warnings in force in Louisiana nowThe forecast where you are
The other tornadoes of August 29, 2021
8 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| August 29 | 6:23 AM CDT | EF1 | Harrison, MS | 2.1 | 150 | $50,000 | ||
| August 29 | 6:25 AM CDT | EF1 | Hancock, MS | 1.7 | 150 | $10,000 | ||
| August 29 | 5:15 PM CDT | EF0 | Harrison, MS | 0.7 | 50 | $100,000 | ||
| August 29 | 6:59 PM CDT | EF0 | Hancock, MS | 10.6 | 75 | $50,000 | ||
| August 29 | 8:56 PM CDT | EF0 | Saint Tammany Parish, LA | 0.9 | 100 | $100,000 | ||
| August 29 | 10:11 PM CDT | EF0 | Hancock, MS | 3.3 | 200 | $250,000 | ||
| August 29 | 10:15 PM CDT | EF0 | Hancock, MS | 2.9 | 200 | $20,000 | ||
| August 29 | 10:37 PM CDT | EF0 | Harrison, MS | 0.5 | 75 | $100,000 |
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.