Alert archive / Arkansas / Mesoscale Discussions in 2008

Mesoscale Discussion 608

April 9, 200814 counties in Arkansas; McCurtain County, Oklahoma; 7 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 9, 2008, 7:28 PM CDT for 14 counties in Arkansas; McCurtain County, Oklahoma; 7 counties in Texas. It was in force for 62 min.

The area

The outline as issued.

The facts

Issued
Apr 9, 2008, 7:28 PM CDT (00:28 UTC)
Expired
Apr 9, 2008, 8:30 PM CDT
In force
62 min
Issued by
the Storm Prediction Center
All 22 counties

Crawford County, AR, Franklin County, AR, Hempstead County, AR, Howard County, AR, Johnson County, AR, Little River County, AR, Logan County, AR, Montgomery County, AR, Pike County, AR, Polk County, AR, Scott County, AR, Sebastian County, AR, Sevier County, AR, Yell County, AR, McCurtain County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Franklin County, TX, Morris County, TX, Red River County, TX, Titus County, TX

The radar

The Western Arkansas radar (KSRX), 93 km from the middle of the area, began a volume at 00:31 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

Shreveport, LA (KSHV), launched 00:00Z, 0.5 hours before the alert went out and 225 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, Shreveport, LA at 00:00Z on 2008-04-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1185 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, Shreveport, LA at 00:00Z on 2008-04-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 206 square meters per square second.1939587897Sfc1 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
1185 J/kg
Mixed-layer CIN
-22 J/kg
Mixed-layer LCL
973 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
206 m²/s²
0-3 km storm-relative helicity
330 m²/s²
Significant tornado parameter
1.8
Supercell composite
7.2

Open this sounding in Storm Lab

The text

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

000 
ACUS11 KWNS 100028
SWOMCD
SPC MCD 100028 
ARZ000-TXZ000-OKZ000-100130-

MESOSCALE DISCUSSION 0608
NWS STORM PREDICTION CENTER NORMAN OK
0728 PM CDT WED APR 09 2008

AREAS AFFECTED...WRN AR INTO THE ARKLATEX

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 100028Z - 100130Z

THE POTENTIAL FOR SEVERE STORMS CAPABLE OF DAMAGING WINDS...LARGE
HAIL AND PERHAPS A COUPLE OF TORNADOES IS EXPECTED TO DEVELOP E OF
WW/S 179 AND 180.  CONVECTIVE TRENDS ARE BEING MONITORED FOR A WW
ISSUANCE.

A WELL-DEFINED SURFACE LOW /MUCH MORE SO THAN MODEL FORECASTS/
CONTINUES TO DEVELOP ENEWD ACROSS E-CNTRL OK IN CONJUNCTION WITH
LEAD SHORT WAVE TROUGH LIFTING NEWD ACROSS REGION.  A CONCENTRATED
AREA OF PRESSURE FALLS IS PRESENT AHEAD OF THIS LOW WHICH IS
ENHANCING: 1)LOW-LEVEL MOISTURE RETURN AND RESULTANT AIR MASS
DESTABILIZATION...AND 2) LOW-LEVEL SHEAR.  THIS HAS RESULTED IN THE
INTENSIFICATION OF ONGOING STORMS WITH ONE SUPERCELL NEARLY
COINCIDENT WITH SURFACE LOW OVER HASKELL COUNTY OK...AS WELL AS
OTHER SUPERCELLS OVER HUGHES COUNTY OK AND CHOCTAW AND PUSHMATAHA
COUNTIES IN SERN OK.

CURRENT DEQUEEN AR PROFILER INDICATES A VERY FAVORABLE KINEMATIC
ENVIRONMENT FOR THE SUSTENANCE OF THESE STORMS WITH 0-1 KM SRH OF
AROUND 300 M2/S2 AND DEEP LAYER SHEAR OF 60-70 KT.  THE PRIMARY
UNCERTAINTY IS HOW FAR E AIR MASS WILL DESTABILIZE GIVEN THE
DEEPER-LAYER CYCLOGENESIS FORECAST OVER THE SRN PLAINS OVERNIGHT. 
REGARDLESS...ONGOING SEVERE STORMS WILL LIKELY MOVE E OF WW/S 179
AND 180 BY 0130Z AND A WW WILL LIKELY BE REQUIRED.

..MEAD.. 04/10/2008

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

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

35809434 36049409 35779321 35019295 33789361 33099433
32929492 32959528 33659522 34129495 34529437

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 9, 8:10 PM CDTTornado WatchSPCHempstead, Howard, Johnson, Little River, Logan, Montgomery and 6 more6 hr
Apr 9, 10:40 PM CDTTornado WatchSPCCrawford, Franklin, Sebastian7 hr
Apr 10, 1:45 AM CDTTornado WatchSPCBaxter, Boone, Cleburne, Conway, Faulkner, Fulton and 16 more8 hr
Apr 10, 3:00 AM CDTMesoscale DiscussionSPCClay, Craighead, Crittenden, Cross, Greene, Mississippi and 1 more60 min
Apr 10, 3:28 AM CDTTornado WatchSPCClay, Craighead, Crittenden, Cross, Greene, Lawrence and 4 more7 hr
Apr 10, 3:54 AM CDTTornado WatchSPCBenton, Carroll, Crawford, Franklin, Hempstead, Howard and 10 more8 hr
Apr 10, 5:55 AM CDTMesoscale DiscussionSPCCrawford, Franklin, Howard, Johnson, Little River, Logan and 4 more65 min
Apr 10, 8:32 AM CDTMesoscale DiscussionSPCAshley, Bradley, Calhoun, Clark, Cleveland, Columbia and 22 more58 min
Apr 10, 8:42 AM CDTTornado WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 19 more7 hr
Apr 10, 9:27 AM CDTMesoscale DiscussionSPCClay, Cleburne, Conway, Craighead, Crittenden, Cross and 16 more2 hr
Apr 10, 9:51 AM CDTTornado WatchSPCClay, Cleburne, Conway, Craighead, Crittenden, Cross and 19 more7 hr
Apr 10, 10:51 AM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Clay, Cleveland and 28 more84 min
Apr 10, 1:41 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Clay, Cleveland and 20 more2 hr
Apr 9, 8:13 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Choctaw, Coal, Garvin and 9 more62 min
Apr 9, 10:01 PM CDTMesoscale DiscussionSPCAtoka, Bryan, Carter, Choctaw, Coal, Garvin and 14 more59 min
Apr 9, 11:22 PM CDTMesoscale DiscussionSPCBeckham, Blaine, Caddo, Canadian, Cleveland, Comanche and 16 more53 min
Apr 10, 1:36 AM CDTMesoscale DiscussionSPCBryan, Carter, Jefferson, Johnston, Love, Marshall and 1 more54 min
Apr 10, 3:30 AM CDTMesoscale DiscussionSPCAtoka, Bryan, Choctaw, Coal, Haskell, Latimer and 8 more60 min
Apr 10, 3:30 PM CDTMesoscale DiscussionSPCAlfalfa, Ellis, Grant, Harper, Kay, Woods and 1 more75 min
Apr 9, 7:44 PM CDTTornado WatchSPCBorden, Brown, Callahan, Coke, Coleman, Concho and 34 more8 hr
Apr 9, 11:46 PM CDTMesoscale DiscussionSPCAndrews, Borden, Brown, Callahan, Coke, Coleman and 35 more59 min

Nearby

Mesoscale Discussions in Arkansas, 2008Mesoscale Discussions in Texas, 2008Mesoscale Discussions in Oklahoma, 2008Every mesoscale discussion in 2008

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.