Alert archive / Arkansas / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 130

April 2, 201225 counties in Arkansas; 20 counties in Oklahoma

The Storm Prediction Center issued this severe thunderstorm watch at Apr 2, 2012, 3:49 PM CDT for 25 counties in Arkansas; 20 counties in Oklahoma. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Apr 2, 2012, 3:49 PM CDT (20:49 UTC)
Expired
Apr 2, 2012, 7:58 PM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 45 counties

Arkansas County, AR, Conway County, AR, Crawford County, AR, Desha County, AR, Faulkner County, AR, Franklin County, AR, Garland County, AR, Grant County, AR, Hot Spring County, AR, Jefferson County, AR, Johnson County, AR, Lincoln County, AR, Logan County, AR, Lonoke County, AR, Monroe County, AR, Montgomery County, AR, Perry County, AR, Polk County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Scott County, AR, Sebastian County, AR, Yell County, AR, Atoka County, OK, Bryan County, OK, Carter County, OK, Coal County, OK, Haskell County, OK, Hughes County, OK, Johnston County, OK, Latimer County, OK, LeFlore County, OK, Love County, OK, Marshall County, OK, McIntosh County, OK, Murray County, OK, Muskogee County, OK, Okfuskee County, OK, Okmulgee County, OK, Pittsburg County, OK, Pontotoc County, OK, Seminole County, OK, Sequoyah County, OK

The radar

The Western Arkansas radar (KSRX), 41 km from the middle of the area, began a volume at 20:52 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
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 2, 4:09 PM CDTSevere Thunderstorm WarningLZKMontgomery, Pike, Polk51 min
Apr 2, 4:30 PM CDTSevere Thunderstorm WarningLZKDesha, Drew, Lincoln30 min
Apr 2, 4:53 PM CDTSevere Thunderstorm WarningLZKPolk, Scott37 min
Apr 2, 5:00 PM CDTSevere Thunderstorm WarningLZKPolk, Scott30 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

Springfield, MO (KSGF), launched 12:00Z, 8.8 hours before the alert went out and 227 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, Springfield, MO at 12:00Z on 2012-04-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 307 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, Springfield, MO at 12:00Z on 2012-04-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 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
307 J/kg
Mixed-layer CIN
-391 J/kg
Mixed-layer LCL
1637 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
146 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 2, 12:15 PM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Chicot, Clark, Cleveland and 17 more90 min
Apr 2, 12:41 PM CDTSevere Thunderstorm WatchSPCBradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 11 more6 hr
Apr 2, 12:50 PM CDTSevere Thunderstorm WatchSPCAshley, Chicot7 hr
Apr 2, 3:18 PM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Clark, Cleveland, Columbia and 28 more117 min
Apr 2, 3:23 PM CDTMesoscale DiscussionSPCAshley, Chicot2 hr
Apr 2, 5:58 PM CDTMesoscale DiscussionSPCArkansas, Clark, Cleveland, Conway, Dallas, Desha and 23 more62 min
Apr 2, 3:00 PM CDTMesoscale DiscussionSPCAlfalfa, Beaver, Beckham, Blaine, Caddo, Canadian and 16 more2 hr
Apr 2, 3:37 PM CDTSevere Thunderstorm WatchSPCAlfalfa, Beaver, Beckham, Blaine, Caddo, Comanche and 16 more7 hr

Nearby

Severe Thunderstorm Watches in Arkansas, 2012Severe Thunderstorm Watches in Oklahoma, 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.