Tornadoes · United States · Kentucky · 2009

EF0 tornado, Almo to Hico, Kentucky, July 4, 2009

From Almo to Hico, this EF0 tornado ran 1.0 miles across Calloway County on July 4, 2009, touching down at 6:29 PM CDT and reaching 50 yards wide. It killed nobody, and did $3,000 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 mphthis tornado

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

  2. EF186 to 110 mph

    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
EF0
Date
July 4, 2009
Touchdown
6:29 PM CDT (23:29 UTC)
Lifted
6:31 PM CDT (23:31 UTC)
On the ground
2 minutes
Path length
1.0 miles (1.6 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$3,000
Crop damage
$10,000
County
Calloway County
Touchdown point
36.731, -88.232
Lift-off point
36.720, -88.220
Record number
0907041729-01

What the Weather Service recorded

Western Kentucky was located in the destabilizing warm sector of a surface low across northern Missouri. Mixed layer CAPE values at or above 1000 j/kg aided thunderstorm intensification as large scale lift was maintained ahead of the surface low. Deep-layer wind shear on the order of 40 to 50 knots contributed to persistent rotating updrafts. A few tornadoes occurred with rotating storms that crossed a warm front draped across southern parts of western Kentucky.

This weak tornado occurred in rural farm country and caused little damage. Several tree limbs and tree tops were blown down. Some field corn was blown over. Peak winds were estimated near 75 mph.

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

The warnings

0 minutes of warning. NWS PAH issued a tornado warning for this county at 23:29 UTC, 0 minutes before the tornado touched down, in force until 23:44 UTC.

The county was under a severe thunderstorm watch, issued at 19:12 UTC and running to 01:00 UTC.

Issued (UTC)ExpiredProductOffice
19:12 UTC01:00 UTCSevere Thunderstorm WatchPAH
23:13 UTC23:45 UTCSevere Thunderstorm WarningPAH
23:29 UTC23:44 UTCTornado WarningPAH
00:19 UTC03:15 UTCFlood AdvisoryPAH

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 19:46 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

11.5 hours before the tornado, 160 km from the path. July 4, 2009.

Skew-T log-pSkew-T log-p diagram, Nashville Metro, TN at 12:00Z on 2009-07-04Temperature 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 -77253, lifted condensation level 1303 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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 2009-07-04The 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 -7 square meters per square second, 0 to 6 km bulk shear 28 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
0 J/kg
Mixed-layer CIN
-77253 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1303 m above ground
0-6 km bulk shear
28 kt
0-1 km bulk shear
0 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
103 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.4 K/km

Open this sounding in Storm Lab

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

0.5 hours after it, 160 km from the path. July 5, 2009.

Skew-T log-pSkew-T log-p diagram, Nashville Metro, TN at 00:00Z on 2009-07-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 238 joules per kilogram, CIN -104, lifted condensation level 1204 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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 2009-07-05The 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 201 square meters per square second, 0 to 6 km bulk shear 28 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
238 J/kg
Mixed-layer CIN
-104 J/kg
Surface CAPE
332 J/kg
Mixed-layer LCL
1204 m above ground
0-6 km bulk shear
28 kt
0-1 km bulk shear
21 kt
0-1 km storm-relative helicity
201 m²/s²
0-3 km storm-relative helicity
297 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.7
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

The radar

The Paducah radar (KPAH), 62 km away, was scanning. The volume nearest the touchdown began at 23:30 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
23:15 UTCTSTM WND DMGMayfieldGraves, KYELECTRICAL LINES DOWN
23:20 UTCTSTM WND DMGDexterCalloway, KYNEAR HWY 1436 TREE LIMBS DOWN AND POWERLINES DOWN
23:27 UTCTSTM WND GST 70MurrayCalloway, KY70 MPH WINDS IN MURRAY...REPORTS OF A ROOF BLOWN OFF A BULDING.
23:29 UTCTORNADO3 Ne AlmoCalloway, KYAN EF0 TORNADO OCCURRED FROM 3 MILES NORTHEAST OF ALMO KENTUCKY TO NEAR HICO KENTUCKY. PEAK WINDS WERE 75 MPH. AVERAGE PATH WIDTH WAS 50 YARDS AND PATH LENGTH WAS 2 MILES. SEVERAL TREE LIMBS AND TREE TOPS WERE DOWNED AND
23:39 UTCTORNADO4 Sw Golden PondTrigg, KYAN EFO TORNADO TOUCHED DOWN 4 MILES SOUTHWEST OF GOLDEN POND KENTUCKY TO 3.5 MILES SOUTHWEST OF GOLDEN POND KENTUCKY. PEAK WIND WAS 70 MPH. AVERAGE PATH WIDTH WAS 50 YARDS AND PATH LENGTH WAS 0.5 MILES. SEVERAL TREE LIMB
23:45 UTCFUNNEL CLOUD8 W CadizTrigg, KY
23:45 UTCTSTM WND DMG3 S CantonTrigg, KYTREE LIMBS DOWNED AROUND CUMBERLAND SHORES...AS WELL AS IN WRANGLERS CAMPGROUND IN THE LAND BETWEEN THE LAKES.
23:50 UTCTSTM WND DMG2 E DonaldsonTrigg, KYTREE LIMBS DOWNED ALONG HIGHWAY 807.
00:08 UTCTSTM WND DMG6 W HerndonTrigg, KYTREES AND POWER LINES DOWN ON THE 2000 BLOCK OF ROARING SPRINGS RD.
00:10 UTCTSTM WND DMG4 W HerndonChristian, KYMETAL STORAGE BUILDING BLOWN ACROSS SIMMONS CEMETERY RD.
00:10 UTCTSTM WND DMGLafayetteChristian, KYTHE GABLE ON A HOUSE IN LAFAYETTE...900 BLOCK ON ROARING SRPINGS ROAD.
00:12 UTCTSTM WND GST 60HerndonChristian, KYOFF DUTY NWS EMPLOYEE ESTIMATES 60 MPH WINDS IN HERNDON KY.
00:13 UTCTORNADO1 Se HerndonChristian, KYEF1 TORNADO WAS NOTED 1.25 MILES SE OF HERNDON OR 11 MILES SSW OF HOPKINSVILLE TO 1.75 MILES SE HERNDON OR 11 MILES S OF HOPKINSVILLE. PEAK WIND WAS ESTIMATED AT 95 MPH. AVERAGE PATH WIDTH WAS 110 YARDS AND PATH LENGTH W

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

This ground now

The live radar over the trackEvery 2009 tornado in KentuckyEvery tornado in Kentucky since 1950Warnings in force in Kentucky nowThe forecast where you are

The other tornadoes of July 4, 2009

2 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 46:39 PM CDTEF0Trigg, KY0.550$3,000
July 47:13 PM CDTEF1Christian, KY0.5110$10,000

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.