Tornadoes · United States · Missouri · 1998

F0 tornado, Hurricane Deck, Missouri, May 21, 1998

This F0 tornado ran 0.7 miles across Camden County on May 21, 1998, touching down at 4:40 PM CDT and reaching 80 yards wide. It killed nobody, and did $30,000 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 mphthis tornado

    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 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. 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
F0
Date
May 21, 1998
Touchdown
4:40 PM CDT (21:40 UTC)
Path length
0.7 miles (1.1 km)
Path width
80 yards (73 m)
Deaths
0
Injuries
0
Property damage
$30,000
County
Camden County
Touchdown point
38.130, -92.830
Lift-off point
38.130, -92.820
Record number
280

What the Weather Service recorded

A weak tornado briefly touched down near Lake Road 5-61 near RY-SEN-SUN Estates and Standing Rock Campground. Several trees were uprooted, with one tree falling on a mobile home. A radio tower in the area was also blown down.

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

The warnings

20 minutes of warning. NWS SGF issued a tornado warning for this county at 21:20 UTC, 20 minutes before the tornado touched down, in force until 22:10 UTC.

Issued (UTC)ExpiredProductOffice
20:56 UTC21:55 UTCSevere Thunderstorm WarningSGF
21:20 UTC22:10 UTCTornado WarningSGF
22:09 UTC23:15 UTCSevere Thunderstorm WarningSGF

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. The outlook in force was issued at 10:39 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.

Springfield, MO (KSGF), 12:00Z

9.7 hours before the tornado, 162 km from the path. May 21, 1998.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 12:00Z on 1998-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2242 joules per kilogram, CIN -143, lifted condensation level 1149 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, Springfield, MO at 12:00Z on 1998-05-21The 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 55 square meters per square second, 0 to 6 km bulk shear 32 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
2242 J/kg
Mixed-layer CIN
-143 J/kg
Surface CAPE
1077 J/kg
Mixed-layer LCL
1149 m above ground
0-6 km bulk shear
32 kt
0-1 km bulk shear
9 kt
0-1 km storm-relative helicity
55 m²/s²
0-3 km storm-relative helicity
86 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.8
0-3 km lapse rate
4.0 K/km

Open this sounding in Storm Lab

Springfield, MO (KSGF), 00:00Z

2.3 hours after it, 162 km from the path. May 22, 1998.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 00:00Z on 1998-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3914 joules per kilogram, CIN -2, lifted condensation level 1231 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Springfield, MO at 00:00Z on 1998-05-22The 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 53 square meters per square second, 0 to 6 km bulk shear 44 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
3914 J/kg
Mixed-layer CIN
-2 J/kg
Surface CAPE
4479 J/kg
Mixed-layer LCL
1231 m above ground
0-6 km bulk shear
44 kt
0-1 km bulk shear
7 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
222 m²/s²
Significant tornado parameter
3.1
Supercell composite
20.2
0-3 km lapse rate
6.8 K/km

Open this sounding in Storm Lab

The radar

The Springfield radar (KSGF), 112 km away, was scanning. The volume nearest the touchdown began at 21:39 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.

This ground now

The live radar over the trackEvery 1998 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

The other tornadoes of May 21, 1998

14 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 2110:35 AM MDTF0Niobrara, WY2.030
May 2110:50 AM MDTF0Scotts Bluff, NE0.530
May 2110:58 AM MDTF0Scotts Bluff, NE3.030
May 2111:03 AM MDTF2Scotts Bluff, NE4.050$10,000
May 2111:17 AM MDTF1Scotts Bluff, NE0.230$4,000
May 2111:30 AM MDTF0Scotts Bluff, NE3.030
May 213:30 PM MDTF0Weber, UT0.130$20,000
May 213:30 PM MDTF0Davis, UT0.130$20,000
May 217:33 PM CDTF0Red Willow, NE0.230
May 216:45 PM MDTF0Perkins, NE0.130
May 218:30 PM CDTF0Monona, IA0.250
May 218:35 PM CDTF0Kearney, NE0.230
May 219:20 PM CDTF1Cass, IA0.540$70,000
May 219:55 PM CDTF0Kearney, NE0.230

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.