Tornadoes · United States · Illinois · 2009

EF0 tornado, Little York, Illinois, May 8, 2009

This EF0 tornado ran 0.5 miles across Warren County on May 8, 2009, touching down at 8:14 PM CDT and reaching 25 yards wide. It killed nobody.

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
May 8, 2009
Touchdown
8:14 PM CDT (01:14 UTC)
Lifted
8:15 PM CDT (01:15 UTC)
On the ground
1 minutes
Path length
0.5 miles (0.8 km)
Path width
25 yards (23 m)
Deaths
0
Injuries
0
County
Warren County
Touchdown point
41.050, -90.750
Lift-off point
41.050, -90.740
Record number
0905081914-01

What the Weather Service recorded

A cold front moved across parts of eastern Iowa and northwest Illinois during the evening of May 8th sparking some showers and thunderstorms.|Some of the storms were severe, producing wind gusts over 58 mph, quarter-sized hail, and a tornado.

A brief tornado was observed for about one minute about 3 miles north of Little York, Illinois around 815 pm on May 8th.

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

The warnings

7 minutes of warning. NWS DVN issued a tornado warning for this county at 01:07 UTC, 7 minutes before the tornado touched down, in force until 01:45 UTC.

The county was under a severe thunderstorm watch, issued at 23:13 UTC and running to 02:52 UTC.

Issued (UTC)ExpiredProductOffice
23:13 UTC02:52 UTCSevere Thunderstorm WatchDVN
00:57 UTC02:00 UTCSevere Thunderstorm WarningDVN
01:07 UTC01:45 UTCTornado WarningDVN

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 00:53 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.

Davenport, (KDVN), 00:00Z

1.2 hours before the tornado, 67 km from the path. May 9, 2009.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2009-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 354 joules per kilogram, CIN -4, lifted condensation level 1505 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, Davenport, at 00:00Z on 2009-05-09The 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 65 square meters per square second, 0 to 6 km bulk shear 63 knots.1939587897117136Sfc1 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
354 J/kg
Mixed-layer CIN
-4 J/kg
Surface CAPE
536 J/kg
Mixed-layer LCL
1505 m above ground
0-6 km bulk shear
63 kt
0-1 km bulk shear
8 kt
0-1 km storm-relative helicity
65 m²/s²
0-3 km storm-relative helicity
167 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.1
0-3 km lapse rate
8.4 K/km

Open this sounding in Storm Lab

Davenport, (KDVN), 12:00Z

10.8 hours after it, 67 km from the path. May 9, 2009.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2009-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1 joules per kilogram, CIN 0, lifted condensation level 546 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, Davenport, at 12:00Z on 2009-05-09The 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 -61 square meters per square second, 0 to 6 km bulk shear 85 knots.1939587897117136Sfc1 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
1 J/kg
Mixed-layer CIN
0 J/kg
Surface CAPE
30 J/kg
Mixed-layer LCL
546 m above ground
0-6 km bulk shear
85 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
-61 m²/s²
0-3 km storm-relative helicity
6 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

The radar

The Quad Cities radar (KDVN), 64 km away, was scanning. The volume nearest the touchdown began at 01:13 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
00:48 UTCTSTM WND GST 704 W Illinois CityRock Island, ILSPOTTER ESTIMATED AT 65 TO 70 MPH WITH PEA SIZE HAIL.
01:15 UTCTORNADO3 N Little YorkWarren, ILSPOTTER REPORTED A TORANADO ON THE GROUND FOR ABOUIT ONE MINUTE AND HAS JUST LIFTED.
01:21 UTCFUNNEL CLOUD1 Nw AlexisMercer, ILSPOTTER ME23 REPORTS FUNNEL CLOUD JUST NORTHWEST OF ALEXIS. NOT ON THE GROUND AT THIS TIME.
01:23 UTCHAIL 13 N Little YorkWarren, ILSPOTTER ALSO REPORTED 45 TO 50 MPH WINDS 2 MILE WEST OF LITTLE YORK.
01:30 UTCTSTM WND DMG3 N MonmouthWarren, ILSPOTTER REPORTED A TELEPHONE POLE DOWN ALONG HWY 67.

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 IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

The other tornadoes of May 8, 2009

45 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 87:53 AM CDTEF1Dade, MO1.9100$35,000
May 88:05 AM CDTEF1Greene, MO3.9100$1.0 million
May 88:14 AM CDTEF1Greene, MO1.875$200,000
May 88:16 AM CDTEF1Polk, MO8.6250$2.0 million
May 88:21 AM CDTEF0Greene, MO3.5100$100,000
May 88:25 AM CDTEF1Taney, MO12.3880$2.6 million
May 88:38 AM CDTEF1Webster, MO3.8400$50,000
May 88:39 AM CDTEF2Douglas, MO2.31,320$200,000
May 88:39 AM CDTEF2Douglas, MO2.5880$20,000
May 88:41 AM CDTEF2Dallas, MO4.34002$2.0 million
May 88:48 AM CDTEF1Douglas, MO1.1200$50,000
May 88:48 AM CDTEF1Ozark, MO1.6440$200,000
May 89:07 AM CDTEF1Wright, MO3.8440$50,000
May 89:19 AM CDTEF0Texas, MO6.8200$50,000
May 89:25 AM CDTEF2Laclede, MO2.0440$500,000
May 89:28 AM CDTEF3Howell, MO2.2800$500,000
May 89:35 AM CDTEF2Howell, MO27.98802$2.5 million
May 89:35 AM CDTEF1Howell, MO10.8880$500,000
May 89:40 AM CDTEF1Texas, MO3.5440$25,000
May 810:25 AM CDTEF1Reynolds, MO1.8440
May 811:20 AM CDTEF0Perry, MO2.250$7,000
May 811:30 AM CDTEF1Jackson, IL3.1100$80,000
May 811:32 AM CDTEF0Jackson, IL0.430
May 812:05 PM CDTEF0Madison, MO0.550
May 812:10 PM CDTEF1Madison, MO0.530
May 81:12 PM CDTEF0Jackson, IL0.140$10,000
May 81:18 PM CDTEF0Franklin, IL0.340
May 81:40 PM CDTEF0Clay, IA0.350
May 81:45 PM CDTEF1Franklin, IL5.5150
May 83:04 PM CDTEF1Barren, KY5.830$50,000
May 84:55 PM EDTEF3Garrard, KY21.1150215
May 85:02 PM EDTEF0McMinn, TN0.120
May 84:15 PM CDTEF1Fentress, TN2.650$150,000
May 85:18 PM EDTEF0Estill, KY0.350$15,000
May 85:58 PM EDTEF2Scott, TN4.5200$90,000
May 86:40 PM EDTEF0Union, TN0.820
May 87:15 PM EDTEF2Claiborne, TN2.2100
May 87:36 PM EDTEF1Grainger, TN9.4100$15,000
May 88:45 PM EDTEF0Washington, TN0.120
May 89:00 PM EDTEF0Dickenson, VA0.6100$5,000
May 89:45 PM EDTEF2Wise, VA1.7120
May 810:25 PM EDTEF0Russell, VA0.120
May 810:27 PM EDTEF2Russell, VA1.1250
May 811:44 PM EDTEF2Alleghany, NC4.92006$200,000
May 811:46 PM EDTEF1Alleghany, NC0.330$5,000

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.