Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 430

April 3, 201222 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 3, 2012, 1:12 PM CDT for 22 counties in Texas. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Apr 3, 2012, 1:12 PM CDT (18:12 UTC)
Expired
Apr 3, 2012, 2:45 PM CDT
In force
93 min
Issued by
the Storm Prediction Center
All 22 counties

Bosque County, TX, Collin County, TX, Dallas County, TX, Denton County, TX, Ellis County, TX, Erath County, TX, Freestone County, TX, Hamilton County, TX, Hill County, TX, Hood County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Limestone County, TX, McLennan County, TX, Navarro County, TX, Parker County, TX, Rains County, TX, Rockwall County, TX, Somervell County, TX, Tarrant County, TX, Wise County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 20 km from the middle of the area, began a volume at 18:13 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 nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 6.2 hours before the alert went out and 29 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, Fort Worth, TX at 12:00Z on 2012-04-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1939 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, Fort Worth, TX at 12:00Z on 2012-04-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 109 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
1939 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
469 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
109 m²/s²
0-3 km storm-relative helicity
92 m²/s²
Significant tornado parameter
0.6
Supercell composite
2.8

Open this sounding in Storm Lab

The text

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

196 
ACUS11 KWNS 031813
SWOMCD
SPC MCD 031812
TXZ000-031945-

MESOSCALE DISCUSSION 0430
NWS STORM PREDICTION CENTER NORMAN OK
0112 PM CDT TUE APR 03 2012

AREAS AFFECTED...N TX

CONCERNING...TORNADO WATCH 133...

VALID 031812Z - 031945Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 133 CONTINUES.

ISOLATED TORNADO THREAT ONGOING -- PARTICULARLY INVOF THE DFW
METROPLEX.

LATEST SURFACE ANALYSIS INDICATES THE WRN EXTENSION OF A W-E OUTFLOW
BOUNDARY IS CURRENTLY LYING OVER THE SRN THIRD OF TARRANT AND DALLAS
COUNTIES -- CONFIRMED BY RECENT VISIBLE SATELLITE IMAGERY.  WHILE A
LARGER CLUSTER OF STORMS CONTINUES ACROSS N TX...SMALL SUPERCELL
STORMS MOVING TOWARD -- AND DEVELOPING NEAR -- THE METROPLEX HAVE
PRODUCED A FEW TORNADOES IN THE PAST HALF HOUR TO HOUR -- LIKELY AS
THEY CROSS/INTERACT WITH THE MORE FAVORABLE VORTICITY/LOW-LEVEL
SHEAR ASSOCIATED WITH THE BOUNDARY.  THOUGH IN GENERAL EXPECT ANY
SINGLE TORNADO TO BE RELATIVELY BRIEF AS STORMS MOVE QUICKLY NEWD
ACROSS THE BOUNDARY...THE ENHANCED POTENTIAL ACROSS THE METROPLEX
AREA ITSELF SUGGESTS CONTINUED/HEIGHTENED RISK FOR A DAMAGING EVENT.

..GOSS.. 04/03/2012

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

ATTN...WFO...FWD...

LAT...LON   33449680 33119571 31329624 31419809 32339824 33339784
            33449680

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 2, 7:17 PM CDTMesoscale DiscussionSPCHansford, Hemphill, Hutchinson, Lipscomb, Ochiltree, Roberts58 min
Apr 2, 9:12 PM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Hardeman, Haskell, Hemphill and 12 more63 min
Apr 2, 10:51 PM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Clay, Jack, Montague, Wichita and 2 more5 hr
Apr 2, 11:45 PM CDTMesoscale DiscussionSPCBrown, Callahan, Coleman, Comanche, Concho, Eastland and 17 more2 hr
Apr 3, 1:14 AM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Clay, Jack, Montague and 7 more2 hr
Apr 3, 3:32 AM CDTMesoscale DiscussionSPCArcher, Baylor, Borden, Brown, Callahan, Clay and 24 more88 min
Apr 3, 8:36 AM CDTMesoscale DiscussionSPCArcher, Bell, Blanco, Bosque, Brown, Burnet and 40 more84 min
Apr 3, 9:18 AM CDTSevere Thunderstorm WatchSPCBosque, Clay, Collin, Comanche, Cooke, Coryell and 33 more8 hr
Apr 3, 11:47 AM CDTMesoscale DiscussionSPCBosque, Collin, Cooke, Coryell, Dallas, Delta and 32 more118 min
Apr 3, 12:08 PM CDTTornado WatchSPCAnderson, Bell, Bosque, Collin, Coryell, Dallas and 30 more9 hr
Apr 3, 1:46 PM CDTMesoscale DiscussionSPCCamp, Cass, Cherokee, Franklin, Gregg, Harrison and 9 more89 min
Apr 3, 2:21 PM CDTMesoscale DiscussionSPCLamar, Montague84 min
Apr 3, 2:36 PM CDTTornado WatchSPCAngelina, Bowie, Brazos, Camp, Cass, Cherokee and 23 more7 hr
Apr 3, 3:05 PM CDTMesoscale DiscussionSPCGrayson, Lamar, Red River85 min
Apr 3, 4:38 PM CDTMesoscale DiscussionSPCAustin, Bastrop, Brazos, Burleson, Caldwell, Fayette and 10 more67 min
Apr 3, 5:00 PM CDTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Delta, Falls and 18 more60 min
Apr 3, 6:53 PM CDTMesoscale DiscussionSPCAnderson, Angelina, Bastrop, Bowie, Brazos, Burleson and 24 more67 min

Nearby

Mesoscale Discussions in Texas, 2012Every mesoscale discussion in 2012

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.