Alert archive / Missouri / Mesoscale Discussions in 2011

Mesoscale Discussion 539

April 23, 20115 states

The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2011, 5:09 PM CDT for 5 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 23, 2011, 5:09 PM CDT (22:09 UTC)
Expired
Apr 23, 2011, 7:15 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 59 counties

Baxter County, AR, Clay County, AR, Fulton County, AR, Randolph County, AR, Alexander County, IL, Gallatin County, IL, Hardin County, IL, Jackson County, IL, Johnson County, IL, Massac County, IL, Pope County, IL, Pulaski County, IL, Saline County, IL, Union County, IL, Williamson County, IL, Ballard County, KY, Caldwell County, KY, Calloway County, KY, Carlisle County, KY, Christian County, KY, Crittenden County, KY, Fulton County, KY, Graves County, KY, Hickman County, KY, Hopkins County, KY, Livingston County, KY, Lyon County, KY, Marshall County, KY, McCracken County, KY, Trigg County, KY, Union County, KY, Webster County, KY, Bollinger County, MO, Butler County, MO, Cape Girardeau County, MO, Carter County, MO, Christian County, MO, Dent County, MO, Douglas County, MO, Howell County, MO, Iron County, MO, Madison County, MO, Mississippi County, MO, New Madrid County, MO, Oregon County, MO, Ozark County, MO, Perry County, MO, Reynolds County, MO, Ripley County, MO, Scott County, MO, Shannon County, MO, Stoddard County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Wayne County, MO, Webster County, MO, Wright County, MO, Lake County, TN

The radar

The Paducah radar (KPAH), 105 km from the middle of the area, began a volume at 22:10 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 12:00Z, 10.2 hours before the alert went out and 248 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 2011-04-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1696 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 2011-04-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 216 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
1696 J/kg
Mixed-layer CIN
-99 J/kg
Mixed-layer LCL
677 m above ground
0-6 km bulk shear
42 kt
0-1 km storm-relative helicity
216 m²/s²
0-3 km storm-relative helicity
243 m²/s²
Significant tornado parameter
1.2
Supercell composite
12.4

Open this sounding in Storm Lab

The text

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

928 
ACUS11 KWNS 232209
SWOMCD
SPC MCD 232209 
KYZ000-TNZ000-INZ000-ILZ000-MOZ000-ARZ000-240015-

MESOSCALE DISCUSSION 0539
NWS STORM PREDICTION CENTER NORMAN OK
0509 PM CDT SAT APR 23 2011

AREAS AFFECTED...SRN/SERN MO INTO SRN IL/WRN KY

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 232209Z - 240015Z

STORMS SHOULD PERSIST FOR SEVERAL MORE HOURS ACROSS SRN MO...MOVING
EWD ACROSS THE MS RIVER BY EVENING WITH MAINLY A HAIL THREAT. A
SEVERE THUNDERSTORM WATCH MAY BE NEEDED.

SURFACE ANALYSIS SHOWS A BOUNDARY ACROSS NRN AR INTO SWRN KY...WITH
RAIN COOLED AIR TO THE N. HOWEVER...A SWLY LOW LEVEL JET IS
RESULTING IN ISENTROPIC LIFT N OF THE BOUNDARY. DEEP LAYER WIND
FIELDS WILL CONTINUE TO FAVOR ORGANIZED SEVERE...AND THE MAIN THREAT
SHOULD BE HAIL GIVEN A RELATIVELY STABLE BOUNDARY LAYER.
HOWEVER...AREAS ALONG THE SURFACE BOUNDARY COULD SEE POTENTIALLY
STRONG/DAMAGING WINDS ACROSS FAR NRN AR...THE MO BOOTHEEL INTO SWRN
KY/FAR SRN IL IF CONVECTION TO THE WEST CAN CONGEAL INTO AN MCS.

..JEWELL.. 04/23/2011

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

ATTN...WFO...OHX...PAH...MEG...LSX...LZK...SGF...TSA...

LAT...LON   36778763 36318940 36149090 36239242 36459342 36989357
            37589272 37719140 37838946 37888841 37788772 37408729
            37038733 36778763

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 22, 7:29 PM CDTMesoscale DiscussionSPCBaxter, Boone, Clay, Fulton, Greene, Izard and 7 more91 min
Apr 22, 8:09 PM CDTMesoscale DiscussionSPCBenton, Carroll, Crawford, Madison, Washington96 min
Apr 22, 9:39 PM CDTMesoscale DiscussionSPCCarroll, Crawford, Franklin, Madison, Sebastian, Washington66 min
Apr 22, 11:04 PM CDTSevere Thunderstorm WatchSPCBaxter, Benton, Boone, Carroll, Madison, Marion and 3 more7 hr
Apr 22, 11:10 PM CDTMesoscale DiscussionSPCBaxter, Benton, Boone, Carroll, Crawford, Franklin and 4 more2 hr
Apr 23, 2:33 AM CDTMesoscale DiscussionSPCBenton, Boone, Carroll, Madison, Marion, Washington87 min
Apr 23, 5:06 AM CDTMesoscale DiscussionSPCBenton, Boone, Carroll, Madison, Marion, Newton and 1 more24 min
Apr 23, 1:04 PM CDTMesoscale DiscussionSPCClay, Craighead, Mississippi86 min
Apr 23, 5:02 PM CDTMesoscale DiscussionSPCBaxter, Clay, Cleburne, Conway, Craighead, Crawford and 21 more58 min
Apr 23, 5:38 PM CDTSevere Thunderstorm WatchSPCBaxter, Benton, Boone, Carroll, Clay, Cleburne and 30 more6 hr
Apr 22, 7:31 PM CDTMesoscale DiscussionSPCAdams, Brown, Cass, Champaign, Christian, Clark and 22 more59 min
Apr 22, 9:20 PM CDTMesoscale DiscussionSPCAlexander, Clay, Clinton, Edwards, Franklin, Gallatin and 23 more55 min
Apr 23, 1:04 AM CDTTornado WatchSPCAlexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 14 more4 hr
Apr 23, 3:41 AM CDTMesoscale DiscussionSPCAlexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 10 more94 min
Apr 23, 4:22 AM CDTMesoscale DiscussionSPCHardin, Pope23 min
Apr 23, 2:30 PM CDTTornado WatchSPCHardin, Massac, Pope5 hr
Apr 23, 10:51 AM CDTMesoscale DiscussionSPCAnderson, Bath, Boone, Bourbon, Boyd, Bracken and 43 more84 min
Apr 23, 2:56 PM CDTMesoscale DiscussionSPCBath, Bourbon, Boyd, Bracken, Carter, Clark and 14 more64 min
Apr 23, 3:39 PM CDTSevere Thunderstorm WatchSPCBoyd, Carter, Greenup, Lawrence4 hr
Apr 23, 6:35 PM CDTMesoscale DiscussionSPCAdair, Anderson, Barren, Bath, Bourbon, Boyle and 37 more55 min

Nearby

Mesoscale Discussions in Missouri, 2011Mesoscale Discussions in Kentucky, 2011Mesoscale Discussions in Illinois, 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.