Alert archive / Arkansas / Tornado Watches in 2010

Tornado Watch 128

May 1, 201035 counties in Arkansas; 11 parishes in Louisiana

The Storm Prediction Center issued this tornado watch at May 1, 2010, 9:53 PM CDT for 35 counties in Arkansas; 11 parishes in Louisiana. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 1, 2010, 9:53 PM CDT (02:53 UTC)
Expired
May 2, 2010, 4:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 46 counties

Arkansas County, AR, Bradley County, AR, Calhoun County, AR, Clark County, AR, Cleburne County, AR, Cleveland County, AR, Columbia County, AR, Conway County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hot Spring County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Jefferson County, AR, Lafayette County, AR, Lincoln County, AR, Lonoke County, AR, Monroe County, AR, Nevada County, AR, Ouachita County, AR, Perry County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Sharp County, AR, Stone County, AR, Union County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Union Parish, LA, Webster Parish, LA

The radar

The Little Rock radar (KLZK), 73 km from the middle of the area, began a volume at 02:56 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
60%
One or more EF2 to EF5 tornadoes
30%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

5 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 1, 10:13 PM CDTFlash Flood WarningLZKGrant, Hot Spring, Lonoke, Pulaski, Saline3 hr
May 1, 10:19 PM CDTSevere Thunderstorm WarningLZKLonoke, Pulaski, White41 min
May 1, 10:23 PM CDTFlash Flood WarningLZKCleburne, Faulkner, Independence, Jackson, Lonoke, Prairie and 4 more3 hr
May 1, 11:32 PM CDTSevere Thunderstorm WarningLZKCleburne, Independence, Jackson, White, Woodruff43 min
May 2, 12:12 AM CDTFlash Flood WarningLZKConway, Garland, Montgomery, Perry, Pope, Van Buren and 1 more3 hr

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Shreveport, LA (KSHV), launched 00:00Z, 2.9 hours before the alert went out and 224 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 00:00Z on 2010-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2524 joules per kilogram.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.
HodographHodograph, Shreveport, LA at 00:00Z on 2010-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 207 square meters per square second.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.
Mixed-layer CAPE
2524 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
952 m above ground
0-6 km bulk shear
68 kt
0-1 km storm-relative helicity
207 m²/s²
0-3 km storm-relative helicity
228 m²/s²
Significant tornado parameter
2.7
Supercell composite
11.3

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 1, 7:11 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 51 more64 min
May 1, 7:30 PM CDTMesoscale DiscussionSPCCraighead, Crittenden, Cross, Greene, Lawrence, Lee and 4 more30 min
May 1, 8:06 PM CDTTornado Watch PDSSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 6 more8 hr
May 1, 8:31 PM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Cleburne, Cleveland and 35 more44 min
May 1, 11:38 PM CDTMesoscale DiscussionSPCArkansas, Clay, Cleburne, Conway, Craighead, Crittenden and 24 more67 min
May 2, 2:33 AM CDTMesoscale DiscussionSPCArkansas, Bradley, Chicot, Clay, Cleveland, Craighead and 16 more87 min
May 2, 6:55 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Cleveland and 5 more2 hr
May 2, 8:01 AM CDTTornado WatchSPCAscension, Assumption, East Carroll, East Feliciana, Jefferson, Lafourche and 13 more7 hr

Nearby

Tornado Watches in Arkansas, 2010Tornado Watches in Louisiana, 2010Every tornado watch in 2010

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.