Alert archive / Arkansas / Mesoscale Discussions in 2011

Mesoscale Discussion 942

May 24, 20114 states

The Storm Prediction Center issued this mesoscale discussion at May 24, 2011, 7:42 PM CDT for 4 states. It was in force for 63 min.

The area

The outline as issued.

The facts

Issued
May 24, 2011, 7:42 PM CDT (00:42 UTC)
Expired
May 24, 2011, 8:45 PM CDT
In force
63 min
Issued by
the Storm Prediction Center

Counties Benton County, AR, Crawford County, AR, Little River County, AR, Polk County, AR, Scott County, AR, Sebastian County, AR, Sevier County, AR, Washington County, AR, McDonald County, MO, Adair County, OK, Cherokee County, OK, Delaware County, OK, Haskell County, OK, LeFlore County, OK, McCurtain County, OK, Sequoyah County, OK, Bowie County, TX, Franklin County, TX, Red River County, TX, Titus County, TX

The radar

The Western Arkansas radar (KSRX), 62 km from the middle of the area, began a volume at 00:45 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

Springfield, MO (KSGF), launched 00:00Z, 0.7 hours before the alert went out and 245 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 00:00Z on 2011-05-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1213 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 00:00Z on 2011-05-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 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
1213 J/kg
Mixed-layer CIN
-94 J/kg
Mixed-layer LCL
941 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
200 m²/s²
Significant tornado parameter
0.7
Supercell composite
6.2

Open this sounding in Storm Lab

The text

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

198 
ACUS11 KWNS 250042
SWOMCD
SPC MCD 250042 
ARZ000-MOZ000-TXZ000-OKZ000-250145-

MESOSCALE DISCUSSION 0942
NWS STORM PREDICTION CENTER NORMAN OK
0742 PM CDT TUE MAY 24 2011

AREAS AFFECTED...ERN OK THROUGH WRN AR AND NERN TX

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 250042Z - 250145Z

SEVERE THREAT IS EXPECTED TO DEVELOP TOWARD WRN AR AND NERN TX
DURING THE EVENING. A NEW TORNADO WATCH WILL LIKELY BE NEEDED FOR
ERN OK...WRN AR AND NERN TX WITHIN THE HOUR.

LATEST OBJECTIVE ANALYSIS INDICATES THE ATMOSPHERE REMAINS
MODERATELY UNSTABLE FROM ERN OK INTO WRN AR AND NERN TX. ONSET OF
NOCTURNAL COOLING WILL CONTRIBUTE TO AT LEAST MODEST BOUNDARY LAYER
STABILIZATION AND INCREASING CONVECTIVE INHIBITION. HOWEVER...LLJ
WILL SHIFT EWD WITH TIME...AND DEEPER LAYER FORCING ASSOCIATED WITH
EJECTING VORT MAX SHOULD HELP TO SUSTAIN STORMS WELL INTO THE
EVENING. LARGE HODOGRAPHS AND EFFECTIVE SHEAR AND 2000 J/KG MLCAPE
WILL CONTINUE TO SUPPORT SUPERCELLS AND BOWING SEGMENTS WITH A
THREAT FOR ISOLATED TORNADOES...LARGE HAIL AND DAMAGING WIND. THE
MORE DISCRETE STORMS ARE EXPECTED TO PERSIST ACROSS SERN OK INTO
NERN TX WITH MIXED MODES LIKELY TO PERSIST FARTHER NORTH.

..DIAL.. 05/25/2011

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

ATTN...WFO...LZK...SGF...SHV...TSA...

LAT...LON   33159522 36029529 36859493 36549384 33359409 33159522

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 24, 8:05 PM CDTTornado WatchSPCBaxter, Benton, Boone, Carroll, Clark, Conway and 30 more7 hr
May 24, 11:24 PM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Clark, Conway, Franklin and 21 more96 min
May 25, 12:48 AM CDTMesoscale DiscussionSPCClay, Craighead, Fulton, Greene, Independence, Jackson and 4 more57 min
May 25, 7:31 AM CDTMesoscale DiscussionSPCClay, Craighead, Crittenden, Cross, Greene, Mississippi and 1 more59 min
May 25, 9:54 AM CDTMesoscale DiscussionSPCBaxter, Boone, Carroll, Clay, Cleburne, Conway and 33 more96 min
May 25, 10:18 AM CDTMesoscale DiscussionSPCFulton, Independence, Izard, Jackson, St. Francis, Sharp and 2 more57 min
May 25, 10:37 AM CDTTornado WatchSPCBaxter, Boone, Carroll, Fulton, Izard, Madison and 5 more7 hr
May 25, 11:02 AM CDTMesoscale DiscussionSPCClay28 min
May 25, 11:52 AM CDTMesoscale DiscussionSPCArkansas, Clark, Clay, Cleburne, Cleveland, Conway and 38 more83 min
May 25, 12:28 PM CDTTornado Watch PDSSPCArkansas, Baxter, Bradley, Calhoun, Clark, Clay and 41 more8 hr
May 25, 1:53 PM CDTMesoscale DiscussionSPCBradley, Calhoun, Clark, Columbia, Dallas, Hempstead and 9 more2 hr
May 25, 2:56 PM CDTMesoscale DiscussionSPCArkansas, Calhoun, Clark, Clay, Cleburne, Cleveland and 33 more94 min
May 25, 3:10 PM CDTMesoscale DiscussionSPCClay95 min
May 25, 3:16 PM CDTTornado WatchSPCAshley, Chicot, Columbia, Lafayette, Miller, Nevada and 1 more7 hr
May 25, 5:56 PM CDTMesoscale DiscussionSPCArkansas, Craighead, Crittenden, Cross, Greene, Lee and 5 more64 min
May 24, 7:07 PM CDTMesoscale DiscussionSPCAndrew, Barton, Bates, Buchanan, Cass, Cedar and 14 more53 min
May 24, 7:26 PM CDTTornado WatchSPCAdair, Barry, Barton, Bates, Benton, Buchanan and 48 more7 hr
May 25, 1:22 AM CDTTornado WatchSPCAudrain, Boone, Callaway, Camden, Christian, Clark and 43 more7 hr
May 25, 4:58 AM CDTMesoscale DiscussionSPCCrawford, Dent, Franklin, Iron, Jefferson, Reynolds and 7 more92 min
May 25, 5:46 AM CDTTornado WatchSPCPerry7 hr
May 25, 11:09 AM CDTTornado Watch PDSSPCBollinger, Butler, Cape Girardeau, Carter, Franklin, Iron and 19 more10 hr
May 25, 1:28 PM CDTMesoscale DiscussionSPCAdair, Audrain, Boone, Caldwell, Callaway, Camden and 44 more92 min
May 25, 2:31 PM CDTTornado WatchSPCClark, Scotland7 hr
May 25, 2:32 PM CDTMesoscale DiscussionSPCAudrain, Lincoln, Marion, Monroe, Montgomery, Pike and 2 more58 min
May 25, 6:25 PM CDTMesoscale DiscussionSPCBollinger, Butler, Cape Girardeau, Mississippi, Perry, Scott and 2 more2 hr
May 24, 11:00 PM CDTMesoscale DiscussionSPCAnderson, Bell, Burnet, Coryell, Falls, Freestone and 6 more60 min
May 24, 11:22 PM CDTSevere Thunderstorm WatchSPCAnderson, Bell, Coryell, Falls, Freestone, Henderson and 7 more5 hr
May 25, 3:10 AM CDTMesoscale DiscussionSPCBastrop, Bell, Blanco, Brazos, Burleson, Burnet and 8 more95 min
May 25, 5:15 PM CDTMesoscale DiscussionSPCAnderson, Austin, Bastrop, Brazos, Burleson, Caldwell and 23 more60 min

Nearby

Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Oklahoma, 2011Mesoscale Discussions in Texas, 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.