Tornadoes · United States · South Carolina · 1998

F2 tornado, Edgefield to Johnston, South Carolina, May 7, 1998

From Edgefield to Johnston, this F2 tornado ran 6.0 miles across Edgefield County on May 7, 1998, touching down at 7:47 PM EDT and reaching 440 yards wide. It killed nobody and injured 2, and did $500,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. F040 to 72 mph

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. F173 to 112 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. F2113 to 157 mphthis tornado

    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. F3158 to 206 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. F4207 to 260 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. F5261 to 318 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
F2
Date
May 7, 1998
Touchdown
7:47 PM EDT (23:47 UTC)
Path length
6.0 miles (9.7 km)
Path width
440 yards (402 m)
Deaths
0
Injuries
2
Property damage
$500,000
County
Edgefield County
Touchdown point
33.830, -81.880
Lift-off point
33.830, -81.780
Record number
808

What the Weather Service recorded

An F3 tornado touched down near SC highway 61 and moved east to SC highway 36 taking down numerous trees and causing major and minor damage to several homes.

An F2 tornado touched down west of Johnston and moved into the community just after 8 pm EDT causing major damage to several homes and businesses.

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

The warnings

1 minute of warning. NWS CAE issued a tornado warning for this county at 23:46 UTC, 1 minute before the tornado touched down, in force until 00:15 UTC.

Issued (UTC)ExpiredProductOffice
22:44 UTC23:45 UTCSevere Thunderstorm WarningCAE
23:10 UTC23:45 UTCTornado WarningCAE
23:46 UTC00:15 UTCTornado WarningCAE
00:07 UTC01:00 UTCTornado WarningCAE
01:53 UTC03:00 UTCSevere Thunderstorm WarningCAE

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 Moderate Risk. The outlook in force was issued at 14:48 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.

Charleston AFB, SC (KCHS), 12:00Z

11.8 hours before the tornado, 199 km from the path. May 7, 1998.

Skew-T log-pSkew-T log-p diagram, Charleston AFB, SC at 12:00Z on 1998-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 280 joules per kilogram, CIN -25, lifted condensation level 931 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, Charleston AFB, SC at 12:00Z on 1998-05-07The 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 94 square meters per square second, 0 to 6 km bulk shear 32 knots.19395878Sfc1 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
280 J/kg
Mixed-layer CIN
-25 J/kg
Surface CAPE
213 J/kg
Mixed-layer LCL
931 m above ground
0-6 km bulk shear
32 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
126 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.4
0-3 km lapse rate
5.0 K/km

Open this sounding in Storm Lab

Charleston AFB, SC (KCHS), 00:00Z

0.2 hours after it, 199 km from the path. May 8, 1998.

Skew-T log-pSkew-T log-p diagram, Charleston AFB, SC at 00:00Z on 1998-05-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 909 joules per kilogram, CIN -107, lifted condensation level 990 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, Charleston AFB, SC at 00:00Z on 1998-05-08The 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 145 square meters per square second, 0 to 6 km bulk shear 40 knots.19395878Sfc1 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
909 J/kg
Mixed-layer CIN
-107 J/kg
Surface CAPE
1674 J/kg
Mixed-layer LCL
990 m above ground
0-6 km bulk shear
40 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
145 m²/s²
0-3 km storm-relative helicity
248 m²/s²
Significant tornado parameter
0.6
Supercell composite
5.4
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

The surface observations

Augusta (DNL), 45 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:53 UTC7871180° 8 kt1006.4
22:53 UTC7671160° 10 kt1004.1
23:53 UTC7471150° 9 kt1004.4
00:53 UTC7670250° 7 kt1005.1

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

This ground now

The live radar over the trackEvery 1998 tornado in South CarolinaEvery tornado in South Carolina since 1950Warnings in force in South Carolina nowThe forecast where you are

The other tornadoes of May 7, 1998

42 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 76:03 AM CDTF1Madison, AL1.550$100,000
May 76:27 AM CDTF1Madison, AL2.080$110,000
May 72:30 PM EDTF1Bradley, TN6.0100$380,000
May 72:00 PM CDTF1Polk, TN to NC14.0100$180,000
May 73:55 PM EDTF0Union, GA9.0100$50,000
May 74:35 PM EDTF1Madison, NC1.350
May 74:35 PM EDTF0Caswell, NC0.5502$200,000
May 75:08 PM EDTF0Oconee, SC0.150
May 75:15 PM EDTF0Alexander, NC5.0300$420,000
May 75:25 PM EDTF1Iredell, NC3.01,320$100,000
May 75:25 PM EDTF0Oconee, SC0.150$10,000
May 75:49 PM EDTF4Caldwell, NC4.01,3202$1.1 million
May 75:50 PM EDTF1Iredell, NC3.0440$1.0 million
May 75:55 PM EDTF2McDowell, NC3.7880$480,000
May 76:03 PM EDTF1Alexander, NC10.0200$450,000
May 76:15 PM EDTF0Davie, NC5.0100
May 76:19 PM EDTF1Surry, NC2.5100$800,000
May 76:24 PM EDTF0Elbert, GA0.130
May 76:25 PM EDTF0Abbeville, SC5.050$30,000
May 76:30 PM EDTF3Forsyth, NC2.0305$50 million
May 76:42 PM EDTF1Greenwood, SC10.0100$70,000
May 76:49 PM EDTF2Lincoln, NC2.0440$210,000
May 77:10 PM EDTF1Davidson, NC0.1100$50,000
May 77:15 PM EDTF3Edgefield, SC5.0880$300,000
May 77:20 PM EDTF1Guilford, NC1.530$100,000
May 77:25 PM EDTF0Lincoln, NC5.050$20,000
May 77:33 PM EDTF1Lincoln, GA0.5100$50,000
May 77:40 PM EDTF1Pittsylvania, VA0.3502$150,000
May 77:41 PM EDTF2Lincoln, GA1.02008$300,000
May 77:45 PM EDTF0Mecklenburg, NC6.050$50,000
May 77:47 PM EDTF1Lincoln, GA1.0100$50,000
May 77:53 PM EDTF2Lincoln, GA0.5200$350,000
May 78:03 PM EDTF0McCormick, SC0.5100
May 77:04 PM CDTF0Seward, KS0.450
May 78:07 PM EDTF1Guilford, NC1.530
May 78:11 PM EDTF1Randolph, NC1.030
May 78:12 PM EDTF1Saluda, SC1.5150$50,000
May 78:15 PM EDTF3Edgefield, SC12.088019$1.0 million
May 78:35 PM EDTF0Greene, OH0.230$10,000
May 78:45 PM EDTF0Aiken, SC3.0100
May 711:48 PM EDTF1New Hanover, NC2.040$40,000
May 712:13 AM EDTF0McCormick, SC0.5100

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.