Alert archive / Arkansas / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 632

September 7, 20125 states

The Storm Prediction Center issued this severe thunderstorm watch at Sep 7, 2012, 5:15 PM CDT for 5 states. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Sep 7, 2012, 5:15 PM CDT (22:15 UTC)
Expired
Sep 8, 2012, 12:00 AM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
65 kt
All 110 counties

Arkansas County, AR, Baxter County, AR, Boone County, AR, Clay County, AR, Cleburne County, AR, Conway County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Desha County, AR, Faulkner County, AR, Fulton County, AR, Garland County, AR, Grant County, AR, Greene County, AR, Hot Spring County, AR, Independence County, AR, Izard County, AR, Jackson County, AR, Jefferson County, AR, Johnson County, AR, Lawrence County, AR, Lincoln County, AR, Logan County, AR, Lonoke County, AR, Marion County, AR, Mississippi County, AR, Monroe County, AR, Montgomery County, AR, Newton County, AR, Perry County, AR, Poinsett County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Randolph County, AR, Saline County, AR, Scott County, AR, Searcy County, AR, Sharp County, AR, St. Francis County, AR, Stone County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR, Yell County, AR, Alexander County, IL, Edwards County, IL, Franklin County, IL, Gallatin County, IL, Hamilton County, IL, Hardin County, IL, Jackson County, IL, Jefferson County, IL, Johnson County, IL, Massac County, IL, Perry County, IL, Pope County, IL, Pulaski County, IL, Saline County, IL, Union County, IL, Wabash County, IL, Wayne County, IL, White County, IL, Williamson County, IL, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Daviess County, KY, Fulton County, KY, Graves County, KY, Henderson County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, McLean County, KY, Muhlenberg County, KY, Todd County, KY, Trigg County, KY, Union County, KY, Webster County, KY, Bollinger County, MO, Butler County, MO, Cape Girardeau County, MO, Carter County, MO, Dunklin County, MO, Mississippi County, MO, New Madrid County, MO, Pemiscot County, MO, Perry County, MO, Ripley County, MO, Scott County, MO, Stoddard County, MO, Wayne County, MO, Crockett County, TN, Dyer County, TN, Gibson County, TN, Haywood County, TN, Lake County, TN, Lauderdale County, TN, Obion County, TN, Shelby County, TN, Tipton County, TN, Weakley County, TN

The radar

The Paducah radar (KPAH), 122 km from the middle of the area, began a volume at 22:18 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
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
90%
One or more gusts of 65 knots or more
50%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Sep 7, 5:52 PM CDTSevere Thunderstorm WarningLZKCleburne, Independence, Jackson, White23 min
Sep 7, 5:54 PM CDTSevere Thunderstorm WarningMEGCraighead, Greene, Lawrence, Randolph51 min
Sep 7, 6:00 PM CDTSevere Thunderstorm WarningLZKBoone, Johnson, Marion, Newton, Searcy45 min
Sep 7, 6:06 PM CDTSevere Thunderstorm WarningLZKJohnson, Pope39 min
Sep 7, 6:23 PM CDTSevere Thunderstorm WarningLZKPope, Searcy, Van Buren26 min
Sep 7, 6:32 PM CDTSevere Thunderstorm WarningLZKJohnson, Logan, Montgomery, Polk, Scott, Yell43 min
Sep 7, 6:35 PM CDTSevere Thunderstorm WarningPAHBollinger, Cape Girardeau, Perry25 min
Sep 7, 6:37 PM CDTSevere Thunderstorm WarningLZKConway, Pope, Van Buren38 min
Sep 7, 6:37 PM CDTSevere Thunderstorm WarningLZKBaxter, Boone, Johnson, Logan, Marion, Newton and 4 more38 min
Sep 7, 6:39 PM CDTSevere Thunderstorm WarningMEGCraighead, Greene, Lawrence, Poinsett51 min
Sep 7, 7:01 PM CDTSevere Thunderstorm WarningPAHEdwards, Wabash, Wayne44 min
Sep 7, 7:03 PM CDTSevere Thunderstorm WarningPAHGallatin, Hardin27 min
Sep 7, 7:08 PM CDTSevere Thunderstorm WarningPAHFranklin, Jefferson, Perry52 min
Sep 7, 7:09 PM CDTSevere Thunderstorm WarningLZKBaxter, Cleburne, Conway, Faulkner, Independence, Marion and 5 more51 min
Sep 7, 7:12 PM CDTSevere Thunderstorm WarningLZKConway, Johnson, Logan, Pope, Yell48 min
Sep 7, 7:12 PM CDTSevere Thunderstorm WarningPAHUnion33 min
Sep 7, 7:14 PM CDTSevere Thunderstorm WarningLZKGarland, Logan, Montgomery, Perry, Scott, Yell46 min
Sep 7, 7:26 PM CDTSevere Thunderstorm WarningPAHFranklin, Jackson, Williamson34 min
Sep 7, 7:26 PM CDTSevere Thunderstorm WarningPAHButler, New Madrid, Scott, Stoddard49 min
Sep 7, 7:28 PM CDTSevere Thunderstorm WarningPAHJackson, Johnson, Union, Williamson32 min
Sep 7, 7:35 PM CDTSevere Thunderstorm WarningPAHBollinger, Perry, Wayne40 min
Sep 7, 7:42 PM CDTSevere Thunderstorm WarningMEGClay, Randolph48 min
Sep 7, 7:43 PM CDTSevere Thunderstorm WarningPAHEdwards, Wabash, Wayne47 min
Sep 7, 7:44 PM CDTSevere Thunderstorm WarningPAHHenderson, Union19 min
Sep 7, 7:45 PM CDTSevere Thunderstorm WarningLZKCleburne, Independence, Izard, Jackson, Stone, White45 min
Sep 7, 7:50 PM CDTSevere Thunderstorm WarningPAHFranklin, Hamilton, Johnson, Pope, Saline, Williamson25 min
Sep 7, 7:51 PM CDTSevere Thunderstorm WarningLZKConway, Faulkner, Perry39 min
Sep 7, 7:53 PM CDTSevere Thunderstorm WarningLZKConway, Garland, Hot Spring, Montgomery, Perry, Pope and 3 more52 min
Sep 7, 7:55 PM CDTSevere Thunderstorm WarningPAHFranklin, Hamilton, Jefferson, Perry, White37 min
Sep 7, 7:59 PM CDTSevere Thunderstorm WarningMEGClay, Greene, Lawrence, Randolph46 min
Sep 7, 8:02 PM CDTSevere Thunderstorm WarningPAHMississippi, New Madrid28 min
Sep 7, 8:06 PM CDTSevere Thunderstorm WarningPAHBollinger, Cape Girardeau, Perry, Scott, Stoddard, Wayne39 min
Sep 7, 8:07 PM CDTSevere Thunderstorm WarningMEGCraighead, Greene, Lawrence38 min
Sep 7, 8:09 PM CDTFlash Flood WarningMEGCraighead3 hr
Sep 7, 8:13 PM CDTSevere Thunderstorm WarningPAHGallatin, Saline, White32 min
Sep 7, 8:15 PM CDTSevere Thunderstorm WarningMEGCraighead, Cross, Poinsett45 min
Sep 7, 8:22 PM CDTSevere Thunderstorm WarningPAHFulton23 min
Sep 7, 8:25 PM CDTSevere Thunderstorm WarningLZKIndependence, Jackson, Woodruff20 min
Sep 7, 8:37 PM CDTSevere Thunderstorm WarningMEGClay, Craighead, Greene, Mississippi38 min
Sep 7, 8:38 PM CDTSevere Thunderstorm WarningPAHAlexander, Johnson, Pulaski, Union37 min
Sep 7, 8:38 PM CDTSevere Thunderstorm WarningPAHDaviess, Henderson, Union37 min
Sep 7, 8:39 PM CDTSevere Thunderstorm WarningLZKFaulkner, Garland, Grant, Hot Spring, Jefferson, Lonoke and 2 more66 min
Sep 7, 8:44 PM CDTSevere Thunderstorm WarningMEGCraighead, Crittenden, Cross, Mississippi, Poinsett, St. Francis46 min
Sep 7, 8:53 PM CDTSevere Thunderstorm WarningMEGLake, Obion52 min
Sep 7, 9:08 PM CDTSevere Thunderstorm WarningMEGCraighead, Mississippi52 min
Sep 7, 9:13 PM CDTSevere Thunderstorm WarningMEGCraighead, Crittenden, Cross, Mississippi, Poinsett, St. Francis47 min
Sep 7, 9:16 PM CDTSevere Thunderstorm WarningPAHDaviess, Henderson, McLean, Webster47 min
Sep 7, 9:19 PM CDTSevere Thunderstorm WarningLZKGrant, Hot Spring56 min
Sep 7, 9:31 PM CDTFlash Flood WarningMEGLake, Obion6 hr
Sep 7, 9:31 PM CDTSevere Thunderstorm WarningMEGCrockett, Dyer, Gibson, Haywood, Lauderdale, Obion and 1 more44 min
Sep 7, 9:34 PM CDTSevere Thunderstorm WarningMEGCrittenden, Mississippi41 min
Sep 7, 9:39 PM CDTSevere Thunderstorm WarningLZKArkansas, Cleveland, Dallas, Grant, Jefferson, Lincoln and 3 more66 min
Sep 7, 9:53 PM CDTSevere Thunderstorm WarningPAHCaldwell, Christian, Hopkins52 min
Sep 7, 10:03 PM CDTSevere Thunderstorm WarningPAHCaldwell, Lyon, Marshall, Trigg42 min
Sep 7, 10:06 PM CDTSevere Thunderstorm WarningMEGCarroll, Crockett, Gibson, Haywood, Henderson, Henry and 3 more24 min
Sep 7, 10:29 PM CDTSevere Thunderstorm WarningPAHChristian, Muhlenberg, Todd, Trigg61 min

Discussions around it

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

The nearest sounding before it

Little Rock, AR (KLZK), launched 12:00Z, 10.3 hours before the alert went out and 247 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, Little Rock, AR at 12:00Z on 2012-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2161 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, Little Rock, AR at 12:00Z on 2012-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 square meters per square second.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.
Mixed-layer CAPE
2161 J/kg
Mixed-layer CIN
-104 J/kg
Mixed-layer LCL
1014 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
30 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.7

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 7, 2:35 PM CDTSevere Thunderstorm WatchSPCBenton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more6 hr
Sep 7, 3:09 PM CDTMesoscale DiscussionSPCBaxter, Cleburne, Conway, Craighead, Cross, Faulkner and 28 more66 min
Sep 7, 3:44 PM CDTMesoscale DiscussionSPCClay, Greene, Mississippi2 hr
Sep 7, 6:06 PM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Crawford, Franklin, Fulton and 9 more84 min
Sep 7, 10:09 AM CDTMesoscale DiscussionSPCClark, Coles, Crawford, Cumberland, Douglas, Edgar and 5 more2 hr
Sep 7, 3:22 PM CDTMesoscale DiscussionSPCCass, Champaign, Christian, Clark, Coles, Crawford and 23 more53 min
Sep 7, 3:41 PM CDTSevere Thunderstorm WatchSPCChristian, Clark, Clay, Coles, Crawford, Cumberland and 8 more6 hr
Sep 7, 2:39 PM CDTMesoscale DiscussionSPCCampbell66 min
Sep 7, 1:41 PM CDTMesoscale DiscussionSPCAudrain, Barry, Barton, Bates, Benton, Boone and 47 more94 min

Nearby

Severe Thunderstorm Watches in Arkansas, 2012Severe Thunderstorm Watches in Kentucky, 2012Severe Thunderstorm Watches in Illinois, 2012Every severe thunderstorm watch in 2012

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.