Tornadoes · United States · Kentucky · 2018

EF1 tornado, Rockcastle, Kentucky, December 31, 2018

This EF1 tornado ran 0.8 miles across Trigg County on December 31, 2018, touching down at 12:35 PM CST and reaching 125 yards wide. It killed nobody, and did $55,000 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
December 31, 2018
Touchdown
12:35 PM CST (18:35 UTC)
Lifted
12:36 PM CST (18:36 UTC)
On the ground
1 minutes
Path length
0.8 miles (1.2 km)
Path width
125 yards (114 m)
Deaths
0
Injuries
0
Property damage
$55,000
County
Trigg County
Touchdown point
36.890, -87.987
Lift-off point
36.892, -87.973
Record number
1812311235-01

The damage survey

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

  • Some trees blown eastward while the majority were blown northward - both uprooted and snapped.

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 narrow line of showers and thunderstorms raced east-northeast across western Kentucky and southwest Indiana, producing pockets of damaging wind and a brief tornado. A deepening low pressure system tracked northeast from Arkansas across the St. Louis area to Indiana. To the east of this low, a warm front lifted north across the lower Ohio Valley in the morning, followed by unseasonably warm and moist air. A trailing cold front then moved east, triggering a narrow line of showers and thunderstorms along the Mississippi River by midday. This line of convection became sporadically severe as it raced across western Kentucky in the afternoon. Heavy rainfall caused some isolated flooding of creeks and roads.

A brief EF-1 tornado touched down just offshore in Lake Barkley near Blue Water Estates. The tornado tracked eastward through part of the subdivision, damaging at least six homes. The damage was minor, consisting mostly of loss of shingles and vinyl siding. There were some broken windows and screens blown in. Three garage doors were blown inward, and one garage lost shingles. A couple of dozen trees were snapped or uprooted. There were two separate eyewitness reports of a tornado. Peak winds were estimated near 90 mph.

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.

Issued (UTC)ExpiredProductOffice
17:00 UTC21:25 UTCWind AdvisoryPAH
18:28 UTC19:00 UTCSevere Thunderstorm WarningPAH
18:36 UTC18:43 UTCTornado WarningPAH
18:48 UTC19:26 UTCSevere Thunderstorm WatchPAH

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 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 16:31 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), 12:00Z

6.6 hours before the tornado, 150 km from the path. December 31, 2018.

Skew-T log-pSkew-T log-p diagram, Nashville Metro, TN at 12:00Z on 2018-12-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -30130, lifted condensation level 470 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Nashville Metro, TN at 12:00Z on 2018-12-31The 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 631 square meters per square second, 0 to 6 km bulk shear 58 knots.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
-30130 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
470 m above ground
0-6 km bulk shear
58 kt
0-1 km bulk shear
52 kt
0-1 km storm-relative helicity
631 m²/s²
0-3 km storm-relative helicity
689 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
2.8 K/km

Open this sounding in Storm Lab

Nashville Metro, TN (KBNA), 00:00Z

5.4 hours after it, 150 km from the path. January 1, 2019.

Skew-T log-pSkew-T log-p diagram, Nashville Metro, TN at 00:00Z on 2019-01-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -36952, lifted condensation level 1184 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Nashville Metro, TN at 00:00Z on 2019-01-01The 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 34 square meters per square second, 0 to 6 km bulk shear 79 knots.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
-36952 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1184 m above ground
0-6 km bulk shear
79 kt
0-1 km bulk shear
47 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
-11 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.5 K/km

Open this sounding in Storm Lab

The radar

The Ft Campbell radar (KHPX), 64 km away, was scanning. The volume nearest the touchdown began at 18:35 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
17:52 UTCTSTM WND DMG5 Sw SymsoniaGraves, KYNWS DAMAGE SURVEY FOUND STRAIGHT LINE WIND DAMAGE WITH ESTIMATED PEAK WINDS OF 75 MPH. THE DAMAGE STARTED AT 11:52 AM CST 5 MILES SW OF SYMSONIA, KY, AND ENDED AT 11:53 AM CST 4.5 MILES W OF SYMSONIA, KY. THE DAMAGE PATH
17:54 UTCTSTM WND DMG4 W SymsoniaGraves, KYSIGNIFICANT DAMAGE TO A BARN ON KY 994 ACROSS FROM THE NORTH GRAVES FIRE DEPARTMENT.
18:10 UTCTSTM WND DMGMurrayCalloway, KYDOWNED TREES REPORTED IN MURRAY AND ON THE NORTH SIDE OF CALLOWAY COUNTY.REPORT OF A DOWNED TREE BLOCKING RADIO ROAD CLOSE TO THE NORTHSIDE BAPTIST CHURCH. SCATTERED POWER OUTAGES ALSO REPORTED IN MURRAY AND NORTH SIDE O
18:15 UTCTSTM WND DMGBentonMarshall, KY8000 REPORTED WITHOUT POWER IN MARSHALL COUNTY.
18:15 UTCTSTM WND GST 593 Ese KirkseyCalloway, KYAWOS STATION CEY, MURRAY KY.
18:35 UTCTORNADO9 Wnw CadizTrigg, KYAN EF1 TORNADO TOUCHED DOWN JUST OFFSHORE IN BARKLEY LAKE NEAR BLUE WATER ESTATES. AT LEAST SIX HOMES DAMAGED...MAINLY LOSS OF SHINGLES AND VINYL SIDING. THERE WERE SOME BROKEN WINDOWS AND SCREENS BLOWN IN. THREE GARAGE
18:38 UTCTSTM WND DMGCadizTrigg, KYNUMEROUS DOWNED TREES AND TREE DAMAGE REPORTED ACROSS THE COUNTY.
18:38 UTCTSTM WND DMGCadizTrigg, KYNUMEROUS POWER OUTAGES REPORTED ACROSS THE COUNTY.
18:45 UTCTSTM WND DMGHawkinsChristian, KYTREES DOWN AND 85MPH WINDS MEASURED IN HAWKINS NEAR HWY 91 AT MILE MARKER 15.
18:45 UTCTSTM WND GST 85HawkinsChristian, KYMEASURED WINDS OF 80 TO 85 MPH IN HAWKINS NEAR HIGHWAY 91 AT MILE MARKER 15.
19:05 UTCTSTM WND GST 682 Sw HopkinsvilleChristian, KY

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

This ground now

The live radar over the trackEvery 2018 tornado in KentuckyEvery tornado in Kentucky since 1950Warnings in force in Kentucky nowThe forecast where you are

The other tornadoes of December 31, 2018

2 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
December 311:43 PM CSTEF1Spencer, IN2.050$50,000
December 313:38 PM ESTEF1Harrison, IN2.2140$20,000

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.