Alert archive / Arkansas / Mesoscale Discussions in 2016

Mesoscale Discussion 202

March 13, 201623 counties in Arkansas; 4 parishes in Louisiana; 4 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 13, 2016, 1:01 PM CDT for 23 counties in Arkansas; 4 parishes in Louisiana; 4 counties in Texas. It was in force for 89 min.

The area

The outline as issued.

The facts

Issued
Mar 13, 2016, 1:01 PM CDT (18:01 UTC)
Expired
Mar 13, 2016, 2:30 PM CDT
In force
89 min
Issued by
the Storm Prediction Center
Chance of a watch
80%
All 31 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Jefferson County, AR, Lafayette County, AR, Lincoln County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Saline County, AR, Union County, AR, Bossier Parish, LA, Claiborne Parish, LA, Union Parish, LA, Webster Parish, LA, Bowie County, TX, Cass County, TX, Marion County, TX, Morris County, TX

The radar

The Shreveport radar (KSHV), 117 km from the middle of the area, began a volume at 18:04 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 (KBAD), launched 12:00Z, 6.0 hours before the alert went out and 110 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 12:00Z on 2016-03-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2016-03-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 141 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
781 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
141 m²/s²
0-3 km storm-relative helicity
157 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

616 
ACUS11 KWNS 131802
SWOMCD
SPC MCD 131801 
ARZ000-LAZ000-TXZ000-131930-

MESOSCALE DISCUSSION 0202
NWS STORM PREDICTION CENTER NORMAN OK
0101 PM CDT SUN MAR 13 2016

AREAS AFFECTED...FAR NE TX...CNTRL/SRN AR...NE/N-CNTRL LA

CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY 

VALID 131801Z - 131930Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...FAST-MOVING SUPERCELL TSTMS ARE EXPECTED TO DEVELOP AROUND
20-21Z. ALL SVR THREATS ARE POSSIBLE INCLUDING VERY LARGE HAIL
/GREATER THAN 2 INCHES/ AND A STRONG TORNADO OR TWO. TORNADO WATCH
LIKELY.

DISCUSSION...INCREASING CU FIELD ACROSS NE TX IS INDICATIVE OF
INCREASED FORCING FOR ASCENT AMIDST THE DESTABILIZING AIRMASS AHEAD
OF THE COMPACT SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW OVER
CNTRL OK. AREAS DOWNSTREAM OF THIS CU FIELD WILL CONTINUE TO
DESTABILIZE UNDER ABUNDANT SUNSHINE AND INCREASING LOW-LEVEL
MOISTURE WITH CONVECTIVE INITIATION EXPECTED BEFORE 20Z. 

ONCE INITIATION OCCURS...STRONGLY SHEARED ENVIRONMENT /EFFECTIVE
BULK SHEAR LIKELY ABOVE 50 KT/ AND MODEST INSTABILITY /MLCAPE AROUND
1000 J PER KG/ WILL SUPPORT FAST-MOVING SUPERCELLS WITH ALL SVR
THREATS POSSIBLE...INCLUDING HAIL GREATER THAN 2 INCHES AND/OR
STRONG TORNADOES. A TORNADO WATCH WILL LIKELY BE NEEDED TO COVER THE
POTENTIAL SVR THREAT.

..MOSIER/HART.. 03/13/2016

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

ATTN...WFO...JAN...LZK...SHV...

LAT...LON   33279128 32869203 32759271 32639372 32589423 32599452
            32649475 33019482 33359459 33779417 34789249 34739158
            33979120 33279128

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 13, 12:35 PM CDTMesoscale DiscussionSPCHoward, Pike, Polk, Scott, Sevier55 min
Mar 13, 12:57 PM CDTTornado WatchSPCCrawford, Franklin, Sebastian6 hr
Mar 13, 2:10 PM CDTTornado WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 37 more5 hr
Mar 13, 3:19 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 31 more86 min
Mar 13, 5:35 PM CDTMesoscale DiscussionSPCCrawford, Franklin, Sebastian, Washington85 min
Mar 13, 5:58 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 38 more92 min
Mar 13, 6:41 PM CDTMesoscale DiscussionSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 40 more94 min

Nearby

Mesoscale Discussions in Arkansas, 2016Mesoscale Discussions in Louisiana, 2016Mesoscale Discussions in Texas, 2016Every mesoscale discussion in 2016

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.