Alert archive / Arkansas / Mesoscale Discussions in 2011

Mesoscale Discussion 848

May 22, 20114 states

The Storm Prediction Center issued this mesoscale discussion at May 22, 2011, 5:18 AM CDT for 4 states. It was in force for 57 min.

The area

The outline as issued.

The facts

Issued
May 22, 2011, 5:18 AM CDT (10:18 UTC)
Expired
May 22, 2011, 6:15 AM CDT
In force
57 min
Issued by
the Storm Prediction Center
All 53 counties

Arkansas County, AR, Calhoun County, AR, Clark County, AR, Cleburne County, AR, Cleveland County, AR, Conway County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Greene County, AR, Hempstead County, AR, Hot Spring County, AR, Independence County, AR, Jackson County, AR, Jefferson County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Mississippi County, AR, Monroe County, AR, Nevada County, AR, Ouachita County, AR, Perry County, AR, Phillips County, AR, Pike County, AR, Poinsett County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, St. Francis County, AR, White County, AR, Woodruff County, AR, Dunklin County, MO, Pemiscot County, MO, Coahoma County, MS, DeSoto County, MS, Tate County, MS, Tunica County, MS, Crockett County, TN, Dyer County, TN, Fayette County, TN, Hardeman County, TN, Haywood County, TN, Lake County, TN, Lauderdale County, TN, Shelby County, TN, Tipton County, TN

The radar

The Little Rock radar (KLZK), 54 km from the middle of the area, began a volume at 10:22 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.

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Little Rock, AR (KLZK), launched 00:00Z, 10.3 hours before the alert went out and 158 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 00:00Z on 2011-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2355 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 2011-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 118 square meters per square second.19395878Sfc1 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
2355 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
791 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
118 m²/s²
0-3 km storm-relative helicity
204 m²/s²
Significant tornado parameter
2.2
Supercell composite
10.6

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

290 
ACUS11 KWNS 221018
SWOMCD
SPC MCD 221018 
TNZ000-MSZ000-MOZ000-ARZ000-221115-

MESOSCALE DISCUSSION 0848
NWS STORM PREDICTION CENTER NORMAN OK
0518 AM CDT SUN MAY 22 2011

AREAS AFFECTED...SOUTHERN/EASTERN AR TO THE ADJACENT MS VALLEY

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 221018Z - 221115Z

POTENTIAL FOR ISOLATED SEVERE HAIL WILL EXIST/POTENTIALLY EXPAND
NORTHEASTWARD THROUGH THE EARLY MORNING ACROSS THE SOUTHERN/EASTERN
HALVES OF AR...TOWARD THE ADJACENT MS VALLEY INCLUDING THE MO
BOOTHEEL/WESTERN TN/WESTERN KY.

COINCIDENT WITH THE SOUTHEASTERNMOST BRANCH OF A SOMEWHAT
SPLIT/MODERATELY STRONG LOW LEVEL JET...ASSOCIATED WARM
ADVECTION/ELEVATED MOISTURE TRANSPORT HAS CONTRIBUTED TO THE
INCREASE OF ELEVATED TSTMS ACROSS SOUTH-CENTRAL AR DURING THE
PREDAWN HOURS. THIS ACTIVITY IS OCCURRING ON THE NORTHERN EDGE OF AN
ELEVATED MIXED LAYER ALOFT...WITH POTENTIALLY STRONG/SEVERE TSTMS
EXPECTED TO EXPAND EAST-NORTHEASTWARD THROUGH THE EARLY MORNING
HOURS TOWARD THE MS VALLEY VICINITY. ADEQUATE SHEAR THROUGH THE
CLOUD BEARING LAYER COUPLED WITH MODERATELY STRONG SOURCE REGION
INSTABILITY WILL SUPPORT SOME TSTMS CAPABLE OF HAIL TO SEVERE
LEVELS...ESPECIALLY THE SOUTHWESTERNMOST UPDRAFTS.

..GUYER.. 05/22/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...PAH...MEG...JAN...LZK...SHV...

LAT...LON   33489401 34969338 36189078 36428926 35318874 33539155
            33489401

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 21, 8:31 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Clark, Cleburne and 45 more89 min
May 22, 7:03 AM CDTSevere Thunderstorm WatchSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Conway and 30 more7 hr
May 22, 11:15 AM CDTMesoscale DiscussionSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Conway and 26 more90 min
May 22, 1:06 PM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Carroll, Fulton, Marion114 min
May 22, 1:09 PM CDTMesoscale DiscussionSPCArkansas, Crittenden, Cross, Grant, Jefferson, Lee and 7 more66 min
May 22, 1:27 PM CDTTornado WatchSPCBenton, Carroll, Crawford, Franklin, Madison, Sebastian and 1 more8 hr
May 22, 3:10 PM CDTMesoscale DiscussionSPCBaxter, Boone, Cleburne, Independence, Izard, Jackson and 9 more65 min
May 22, 3:24 PM CDTTornado WatchSPCBaxter, Boone, Clay, Cleburne, Conway, Craighead and 22 more6 hr
May 22, 3:48 PM CDTMesoscale DiscussionSPCBenton, Carroll, Crawford, Franklin, Madison, Washington117 min
May 22, 5:21 PM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Clay, Cleburne, Conway and 22 more54 min
May 22, 6:10 PM CDTMesoscale DiscussionSPCBenton, Carroll, Crawford, Franklin, Madison, Washington65 min
May 21, 7:18 PM CDTMesoscale DiscussionSPCAndrew, Buchanan, Caldwell, Carroll, Chariton, Clay and 23 more57 min
May 21, 8:55 PM CDTMesoscale DiscussionSPCAtchison65 min
May 22, 4:41 AM CDTMesoscale DiscussionSPCAdair, Audrain, Boone, Clark, Knox, Lewis and 9 more2 hr
May 22, 10:53 AM CDTMesoscale DiscussionSPCAdair, Audrain, Bates, Benton, Boone, Caldwell and 36 more2 hr
May 22, 12:51 PM CDTTornado WatchSPCAdair, Audrain, Bates, Boone, Caldwell, Callaway and 47 more10 hr
May 22, 12:55 PM CDTMesoscale DiscussionSPCAnderson, Bedford, Bledsoe, Blount, Bradley, Campbell and 51 more65 min
May 22, 1:18 PM CDTSevere Thunderstorm WatchSPCAnderson, Bedford, Bledsoe, Blount, Bradley, Campbell and 64 more7 hr
May 22, 3:44 PM CDTMesoscale DiscussionSPCAnderson, Blount, Campbell, Carter, Claiborne, Cocke and 17 more61 min
May 22, 6:26 PM CDTMesoscale DiscussionSPCCarter, Cocke, Greene, Hamblen, Hawkins, Johnson and 3 more2 hr

Nearby

Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Tennessee, 2011Mesoscale Discussions in Mississippi, 2011Every mesoscale discussion in 2011

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.