Tornadoes · United States · Mississippi · 2017

EF1 tornado, Petal, Mississippi, August 30, 2017

This EF1 tornado ran 1.3 miles across Forrest County on August 30, 2017, touching down at 11:41 AM CDT and reaching 160 yards wide. It killed nobody, and did $200,000 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.

  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.

The record

Rating
EF1
Date
August 30, 2017
Touchdown
11:41 AM CDT (16:41 UTC)
Lifted
11:45 AM CDT (16:45 UTC)
On the ground
4 minutes
Path length
1.3 miles (2.0 km)
Path width
160 yards (146 m)
Deaths
0
Injuries
0
Property damage
$200,000
County
Forrest County
Touchdown point
31.346, -89.269
Lift-off point
31.364, -89.271
Record number
1708301041-01

The damage survey

12 damage points were recorded along this path by NWS JAN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 90 mph.

  • few trees uprooted, part off roof off building, fence down
  • trees uprooted, snapped, roof dmg to building.
  • few trees uprooted, one tree on 2 vehicles, lines down.

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

The remnants of Hurricane Harvey moved across the ArkLaMiss region on August 30th and 31st and brought gusty winds and rain to the region. A few tornadoes also occurred on the 30th. As Harvey decreased to a depression on the 31st, gusty winds still remained across portions of the region. This resulted in some downed trees outside of any shower activity.

This tornado touched down in Petal along West Central Ave. Here, two businesses sustained minor roof damage with a portion of the roof peeled off. Several trees were uprooted and a fence was blown down. As the tornado moved northward, a few more trees were downed along with limbs broken off trees. Along Stevens St, a large tree crushed two vehicles. More minor tree damage occurred across several streets before the tornado crossed the intersection of Highway 11 and the Evelyn Gandy Parkway, where more trees were damaged. The tornado lifted after it crossed into the wooded area north of the Parkway near the Leaf River. Maximum winds were around 90 mph.

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

The warnings

58 minutes of warning. NWS JAN issued a tornado warning for this county at 15:43 UTC, 58 minutes before the tornado touched down, in force until 16:45 UTC.

The county was under a tornado watch, issued at 15:23 UTC and running to 23:00 UTC.

Issued (UTC)ExpiredProductOffice
14:50 UTC15:45 UTCSevere Thunderstorm WarningJAN
15:05 UTC15:45 UTCTornado WarningJAN
15:23 UTC23:00 UTCTornado WatchJAN
15:38 UTC16:30 UTCTornado WarningJAN
15:43 UTC16:45 UTCTornado WarningJAN
16:50 UTC17:15 UTCTornado WarningJAN
17:18 UTC17:35 UTCTornado WarningJAN
18:14 UTC19:00 UTCSevere Thunderstorm WarningJAN

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 Enhanced Risk, with a 0.10 chance of a tornado within 25 miles. The outlook in force was issued at 16:27 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

4.7 hours before the tornado, 130 km from the path. August 30, 2017.

Skew-T log-pSkew-T log-p diagram, Slidell Radar S, LA at 12:00Z on 2017-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1853 joules per kilogram, CIN -7, lifted condensation level 550 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Slidell Radar S, LA at 12:00Z on 2017-08-30The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 270 square meters per square second, 0 to 6 km bulk shear 33 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
1853 J/kg
Mixed-layer CIN
-7 J/kg
Surface CAPE
2134 J/kg
Mixed-layer LCL
550 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
38 kt
0-1 km storm-relative helicity
270 m²/s²
0-3 km storm-relative helicity
310 m²/s²
Significant tornado parameter
2.2
Supercell composite
13.7
0-3 km lapse rate
5.0 K/km

Open this sounding in Storm Lab

Slidell Radar S, LA (KSIL), 00:00Z

7.3 hours after it, 130 km from the path. August 31, 2017.

Skew-T log-pSkew-T log-p diagram, Slidell Radar S, LA at 00:00Z on 2017-08-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 251 joules per kilogram, CIN -15, lifted condensation level 1133 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Slidell Radar S, LA at 00:00Z on 2017-08-31The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 163 square meters per square second, 0 to 6 km bulk shear 31 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
251 J/kg
Mixed-layer CIN
-15 J/kg
Surface CAPE
1402 J/kg
Mixed-layer LCL
1133 m above ground
0-6 km bulk shear
31 kt
0-1 km bulk shear
27 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
217 m²/s²
Significant tornado parameter
0.1
Supercell composite
3.2
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

The radar

The Jackson/Brandon,MS radar (KDGX), 123 km away, was scanning. The volume nearest the touchdown began at 16:40 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)ReportWhereCountyRemark
15:00 UTCTSTM WND DMG8 W PurvisLamar, MSA FEW TREES DOWN NEAR BEACH AND RL ANDERSON ROADS, POSSIBLE TORNADO.
15:04 UTCTORNADO8 W PurvisLamar, MSTHIS TORNADO TOUCHED DOWN IN A WOODED AREA JUST NORTH OF PURVIS TO COLUMBIA ROAD, NEAR THE INTERSECTION OF B YOUNG ROAD. THIS AREA WAS INACCESSIBLE DUE TO POWER CREWS WORKING TO REPAIR A DOWNED TRANSMISSION LINE. BASED O
15:43 UTCHEAVY RAIN 26 Nnw PurvisLamar, MSHIGHWAY 589 WAS COVERED WITH 1-2 INCHES OF WATER AND IT WAS STILL RISING.
16:23 UTCTSTM WND DMG9 Nw LumbertonLamar, MSSOFTWOOD TREES UPROOTED, STORM SURVEY ESTIMATED WINDS OF 73MPH.
16:40 UTCTORNADO1 Wnw PetalForrest, MSTORNADO REPORTED IN DOWNTOWN PETAL. TWO BUSINESSES ON MAIN STREET WITH MAJOR ROOF DAMAGE. SEVERAL TREES DOWN ON HIGHWAY 11 AT EVELYN GANDY PARKWAY.
16:40 UTCTORNADO1 Wnw PetalForrest, MSTHIS TORNADO WAS RATED EF1 TORNADO WITH ESTIMATED MAXIMUM WIND SPEED 90 MPH. TWO BUSINESSES ON MAIN STREET WITH MAJOR ROOF DAMAGE. SEVERAL TREES DOWN ON HIGHWAY 11.
16:41 UTCTORNADO1 W PetalForrest, MSTHIS TORNADO TOUCHED DOWN IN PETAL ALONG WEST CENTRAL AVE. HERE, TWO BUSINESSES SUSTAINED MINOR ROOF DAMAGE WITH A PORTION OF THE ROOF PEELED OFF. SEVERAL TREES WERE UPROOTED AND A FENCE WAS BLOWN DOWN. AS THE TORNADO MO
16:42 UTCTORNADO1 Nw PetalForrest, MSTREE ON A HOUSE.
17:32 UTCTSTM WND DMG5 N BassfieldJefferson Davis, MSTREE DOWN ON A VEHICLE ON WILLIAMS LN.
17:35 UTCTORNADO5 N BassfieldJefferson Davis, MSTHIS BRIEF TORNADO TOUCHED DOWN AT WILLIAMS LN, JUST OFF HIGHWAY 35, AND TRACKED NORTH FOR ABOUT 1 MILE. AT WILLIAMS LN, A LARGE TREE WAS BLOWN DOWN ONTO A TRUCK, THE TREE WAS LAID TO THE WEST. OTHER LARGE LIMBS AND TREE

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2017 tornado in MississippiEvery tornado in Mississippi since 1950Warnings in force in Mississippi nowThe forecast where you are

The other tornadoes of August 30, 2017

6 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 301:46 AM CDTEF0Harrison, MS0.130
August 302:16 AM CDTEF0Jackson, MS1.0100
August 3010:04 AM CDTEF1Lamar, MS1.7100$150,000
August 3010:12 AM CDTEF1Pearl River, MS4.6100
August 3011:31 AM CDTEF0Jackson, MS2.3100
August 3012:35 PM CDTEF0Jefferson Davis, MS1.150$15,000

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.